An independent video game company has found success with marketing tactics often found in the music industry. Wolfire Games is offering a pay-what-you-want download bundle from its web site. The Humble Indie Bundle consists of five classic indie games with a combined retail value of $80. Contributors can pay via Paypal, Amazon.com or Google Checkout.

“It has sold far, far better than we expected,” Wolfire co-founder Jeffrey Rosen told Billboard in an email. “We had a lot of scenarios in mind before we launched it, but the reality is better than we dared hope.”

Here are some of the stats shared at the company’s blog:

• As of Tuesday afternoon, the bundle had raised $956,278 from 106,704 contributors – an average of $8.96 – in about seven days. That may seem low for a bundle whose individual components have a retail value of $80, but Rosen is clearly happy with the results. The key takeaway here is that one should not compare the retail value to the average donated value. Because net revenue is the key metric, a far better comparison is total revenue raised relative to the cost of distribution. In this case, the cost of distribution equals the cost of the traffic Wolfire has generated. According to Rosen, Wolfire has served over 60 terrabytes of data through the first six days of the Humble Bundle promotion.

• Linux users donated an average of $14.01 compared to $9.87 by Mac users and $7.47 by Windows users. One contributor gave $1,000, two gave $500, one gave $400 and five gave between $210 and $255.

• 25% of people who acquired the bundle did so through P2P, not the company’s site (where it was DRM-free and available for download).

Wolfire has found the promotional value of its pay-what-you-want offer has added to its actual monetary impact. “We are getting coverage from all sorts of places -- not just in the gaming community,” wrote Rosen. Word obviously got out. On Monday afternoon, it had raised $742,910 from 86,046 contributors – an average of $8.63 – over the previous six days. So, on the final day of the promotion Wolfire raised over $200,000 from 20,000 contributors.

Indeed, creative pay-what-you-want offers tend to spread through word of mouth beyond an artist’s core group of fans. As a result, what looks like a gimmicky promotion can turn out to be a cost-effective way to generate Web traffic and gain new fans.

The pay-what-you-want tactic was popularized by Radiohead’s “In Rainbows” self-release and has been frequently copied – usually by independent artists. Bandcamp offers a “pay what you want” (with a minimum price) option to artists. Similarly, Noisetrade builds a tip jar into its platform. Topspin says it will have a pay-what-you-want function later this year.