For those of you with scratched/unplayable Halo 3 Discs..
http://assets.xbox.com/en-us/support/replacementdisk_orderform.pdf
Looks like it's free if you have the Limited Ed version.
http://assets.xbox.com/en-us/support/replacementdisk_orderform.pdf
Looks like it's free if you have the Limited Ed version.