Sparkle is a tool which can repair broken Gentoox installations automatically. More specifically, it is a reiserfs filesystem repairer. Basically, it searches for rootfs files on your Xbox, then fixes them. It is also compatible with native installations!

Necessity is the mother of all invention, I broke one of my installations of Gentoox today by hard powering down (with the power switch). After creating "uglyfsck" on another Xbox, then running it on my broken Xbox and discovering it actually worked, I decided it might be useful for other Gentoox users too. So after a name change and some polishing, here it is: "Sparkle".

ALWAYS read the manual. While this tool worked for me, it is not guaranteed to work for you - infact, it may make things worse. Obviously, there is no guarantee with this since it's released under the GPL.

*Update*
Just thought I'd add, this is based off the new Stardust with HDTV and focus support. So if you want to see if the new Stardust will work with your setup, it might be an idea to try this. Purely up to you though!