The inimitable Internet Archive already contains an embarrassment of riches, cataloging old versions of millions and millions of websites, but we're rather enamored with its Console Living Room, launched yesterday.
As the intellectual property protections on old games expired, the Internet Archive swooped in to make them freely playable online in your browser. The site is currently host to a trove of games from such classic consoles as the Atari, the ColecoVision, and even an oddball system we'd never heard of called the Astrocade.
At the time of this writing, there are 988 games freely available for download and in-browser play!