Olivia Newton-John Sings 'Summer Nights' With Rescued Chilean Miner
Olivia Newton-John rehearses at 'Kaleidoscope' at Verizon Center on November 16, 2009 in Washington, DC. Getty

As Billboard celebrates 1,000 No. 1s in the Billboard Hot 100's storied archives, it's inevitable that certain past toppers require an extra pause before triggering recognition.

Despite all 1,000 titles having earned the honor of, at least for one week, reigning as the most popular song in the country, subsequent decades have not treated all such cuts equally.

While some songs remain pop culture, and radio, staples - Aretha Franklin's "Respect," the Eagles' "Hotel California," Bon Jovi's "Livin' on a Prayer," for instance - others live on more as historic footnotes, known better to avid chart-watchers and music collectors than audiences at large.

With the Hot 100's No. 1 counter at 1,000, which more obscure past leaders deserve a renewed spotlight?

Boston-based Barry Scott, the subject of yesterday's Chart Beat Q&A upon the 25th anniversary of his retro radio program, "The Lost 45s," offered Billboard his expert insight on which songs have rarely received regular radio play following their Hot 100 chart lives.

As Scott notes, scanning 1,000 No. 1s for hidden gems requires more than a little organization. Scott negated three categories that generally no longer receive strong airplay simply by their short-shelf-life natures: novelty songs ("Disco Duck," "The Streak," "Purple People Eater,"); songs by middle-of-the-road artists whose pop careers waned in the wake of the British Invasion (Dean Martin, Perry Como, Frank Sinatra); and, instrumentals, a gentle genre that decreased in hits every decade until virtually none aired on top 40 radio ("Stranger on the Shore," "Stripper," "Chariots of Fire").

Remaining are songs that you might hear on Scott's program, which spotlights an incredibly deep library, but not likely often on most oldies stations or other formats' '70s, '80s or '90s flashback weekends.

Below are 15 of Scott's choices (and trivia nuggets), from "(You're) Having My Baby" to "Ice Ice Baby."

Please feel free to add to the list in the comments section below or by e-mailing askbb@billboard.com.

"The Candy Man," Sammy Davis Jr., 1972
Originally heard in the movie "Willy Wonka and the Chocolate Factory" (sung by Aubrey Woods), this hit version spent three weeks at No. 1, based largely on adult-leaning airplay and childhood allowance money (that didn't go to candy bars). "The fact that many inferred a drug reference from the innocent lyrics may have spurred sales among less youthful audiences," Scott adds.

"The Night the Lights Went Out in Georgia," Vicki Lawrence, 1973
Written by then-husband Bobby Russell ("Honey"), who coaxed Lawrence into the studio to record this busy storyline-on-vinyl after Sonny Bono had turned it down for Cher (see "Half-Breed," below), the song rose from No. 100 to 1 in two months. A TV movie followed, as did two other charted hits by Lawrence, but the "Carol Burnett Show" star is often reluctant, understandably, considering her ex's involvement, to discuss her secondary career, says Scott.

"Half-Breed," Cher, 1973
Written specifically for Cher, her songs from this era were hand-chosen by Bono and producer Snuff Garrett. Cher told Scott that she tried to break out of a near-novelty/story-song mold ("Gypsys, Tramps & Thieves"), but it took until her late-'80s comeback ("If I Could Turn Back Time") for such a segue. Why did Bono turn down "The Night the Lights Went Out in Georgia" for Cher? He thought that it would offend the South.

"Seasons in the Sun," Terry Jacks, 1974
The song had bounced around for years, including a recording by the Kingston Trio 10 years earlier. Jacks had produced a version for the Beach Boys, which went unreleased. For "pre-teens in 1974, the song was pure poetry," says Scott. When Scott brought Jacks to Boston a few years ago, the adult crowd was "hushed, yet mouthing every word fanatically," Scott remembers. Proving sales can equal sails, Jacks lives on a boat called "Seasons in the Sun," funded by proceeds from this multi-million-selling hit.

"(You're) Having My Baby," Paul Anka with Odia Coates, 1974
Later changed to the more politically correct "Having Our Baby," Anka told Scott that the song was simply a joyous ode to his wife and their four daughters. Its lyrics, however, created much controversy, helping propel it to the top. Additional fun fact: playing when TV's fictional "WKRP in Cincinnati" switched formats to rock was a choral version of the song.

"Thank God I'm a Country Boy," John Denver, 1975
The late singer/songwriter/actor deftly straddled pop, folk and country with successful results - and how fun are his holiday duets with the Muppets? Still, this rollicking song and his three other No. 1s - "Sunshine on My Shoulders," "Annie's Song" and "I'm Sorry" - are not often programmed. In 2009, Juno-nominated and former "Canadian Idol" finalist Carly Rae Jepsen sent her cover of "Sunshine" to No. 15 on the Canada AC chart.

"I Write the Songs," Barry Manilow, 1976
Written by Bruce Johnston of the Beach Boys - not Manilow, despite the title - the ballad was first recorded by David Cassidy, then Captain & Tennille (on their debut LP) before Manilow, whose two other No. 1s - "Looks Like We Made It" and "Mandy" - also receive limited airplay in 2011. (Peter Griffin and his "Family Guy" Quahog cohorts, are, however, rabid Barry-oke-addicted Manilow maniacs).

"You Light Up My Life," Debby Boone, 1977
Although it spent 10 weeks at No. 1, this ballad just doesn't fit on up-tempo based classic hits stations. Boone told Scott that she sang this song to God and the songwriter, Joe Brooks, didn't like her non-secular interpretation when he found out about her divine inspiration.

"Physical," Olivia Newton-John, 1981
Though remade last year on Fox's "Glee" (with Jane Lynch and Newton-John herself), "Physical," which spent 10 weeks at the summit, had been largely dormant at radio for years. As its original performer told Scott, the video might have contributed greatly to its hibernation, with its now clearly dated fashion stamp. The clip's exercise motif, however, helped dispel potentially controversial images of lines such as "there's nothing left to talk about, unless it's horizontally."

"Mickey," Tony Basil, 1982
The group Racey originally recorded this song as "Kitty," a fitting first title since the composition has had more than one life. Choreographer Toni Basil, who had worked on such '60s TV music shows as "Shindig" and "Hullabaloo," covered the song and it clawed its way to the top. With Avril Lavigne's current "What the Hell" a sonic descendant, the song still occasionally litters '80s specialty programming.

"Batdance," Prince, 1989
Although not included in the movie directed by Tim Burton, "Batdance" became Prince's fourth No. 1 based largely on the film's impact. Written in "just a few hours," notes Scott, the song mashes up dialogue and sounds from the movie. Prince played various "Batman" characters in the song's clever video.

"Blame It on the Rain," Milli Vanilli, 1989
The duo's third No. 1 went the same way as its first two when it was revealed that neither Fabrice Morvan nor Rob Pilatus had actually sung lead vocals on the songs. The public "seemed disturbed by this fact, demanding money back, initiating lawsuits and Grammy Award withdrawals," recounts Scott. In the end, all three leaders - "Girl I'm Gonna Miss You," "Baby Don't Forget My Number" and this song - are catchy ... just sung by someone else, namely Charles Shaw.

"Step by Step," New Kids on the Block, 1990
At the peak of their worldwide success, the Kids secured a third No. 1 with this song, all of which were written and produced by Maurice Starr. Despite this year's touring comeback with Backstreet Boys, and the group's first top 40 hit in 2008 ("Summertime," No. 36) since 1992, all three No. 1s ("I'll Be Loving You (Forever)" and "Hangin' Tough" reigned in 1989) are largely avoided by American radio.

"Ice Ice Baby," Vanilla Ice, 1990
Another song revived by "Glee" (in the same episode in which the cast covered "Physical") reached No. 1 alongside the controversy that the rapper, aka, Robbie Van Winkle, once claimed to have written it himself. Queen and David Bowie begged to differ and later received writing credits for the sampling of their "Under Pressure" bass line.

"Justify My Love," Madonna, 1991
With a video banned at MTV, songwriting co-credit with Lenny Kravitz (and a co-credit lawsuit which added a third name), this new track on "The Immaculate Collection" spent two weeks at No. 1. Most customers bought the song as the first real video single. The "images ultimately outweighed the content," says Scott, and the song has become a somewhat overlooked release from Madonna, whose more lasting radio-friendly No. 1s (of 12 in all) include "Open Your Heart," "Like a Prayer" and "Take a Bow."