2D Boy seems quite satisfied with the results of its "pay what you want" World of Goo experiment. In celebration of Goo's first birthday, developer 2D Boy allowed people to determine the game's price at checkout. The result: 57,000 sales at an average price of $2.03. Although a significant number took the game at one penny (really, people?!), the developer's graph of purchases reveals that almost as many bought the game for $1. There were also sales spikes at $5 and $10.

What's probably most interesting is that while this experiment was going on at 2D Boy's site, sales on Valve's digital distribution service, Steam, went up by 40 percent from the previous week, at $20 a pop. WiiWare sales increased by nine percent, but the devs aren't sure if that was just normal fluctuation.

2D Boy also put up a survey asking why customers decided on the amount they paid. The top answer, at 22.7 percent, was "That's All I can Afford Right Now." We seriously hope those weren't the penny payers, because that's just tragic (even in a recession). A close second, at 22.1 percent, were people who wanted to support the pay-what-you-want model.

This article was originally published on Joystiq.

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