Ke$ha, "TiK ToK"
After lending her vocals to Flo Rida's "Right Round," Ke$ha offers her own fun and frivolous ode to a wild night out. "TiK ToK" finds the 22-year-old singing teasingly about excess pleasures, from drinking ("Ain't got a care in the world but I got plenty of beer") to men ("We kick 'em to the curb unless they look like Mick Jagger"). In case that weren't enough, Ke$ha also alludes to brushing her teeth with a bottle of Jack Daniel's and name-drops Diddy, who provides a quick cameo for good measure. The song is a love letter to DJs everywhere, with hand claps that build to a crescendo of pure, infectious dance-pop. Ke$ha's debut album is due in late 2009, and with this first solo effort, the singer reveals a knack for getting the party started.-Kelsey Paine