We're not suggesting you try this, since, in addition to voiding your warranty, you run a real chance of bricking your Xbox 360, but we just thought we'd mention it: a new firmware hack for the 360, known affectionately as "Xtreme firmware for TS-H943 Xbox 360" by its creators, can apparently mod your 360's DVD drive so that it'll work with just about anything you can put in it, including "backup" discs made for both the original Xbox and the 360. According to about seven pages of posts on an Xbox forum, the hack does indeed seem to work, but only with 360s that have a Toshiba/Samsung DVD drive, and only if you're willing to take the time to follow the instructions very carefully. We'll pass -- at least until there's a version that lets the 360's HD DVD drive output 1080p video from protected discs over component cables. Make that work, and we'll happily risk bricking our 'box.
[Thanks to everyone who sent this in!]