Haven't seen a magic lantern thread...but if you don't have it..try it out..
Here are the sites I used.
Step 1. Make sure your up to date on your canon firmware.
1.0.9
http://web.canon.jp/imaging/eosd/firm-e/eosdigital7/firmware.html
step 2.
http://magiclantern.wikia.com/wiki/550d_install
Step 3. Copy the files on the memory card and install the newest build.
http://www.chungdha.com/2011/02/follow-focus-with-magic-lantern.html
This setup is very helpful and allows you to turn off the automatic gain control. I just started using it today and it seems like it will help a ton!
*NOTE PLEASE DO RESEARCH YOURSELF. I AM JUST SUPPLYING THE LINKS. IF YOU MESS YOUR CAMERA UP, IT'S NOT MY FAULT. THAT'S ON YOU HOMEBOY.