It asks for credit card, though...Not Sure if Right Place But thought got lots out of this thread so be nice to try give back.
While trying to sort out my Xbox account thought I'd check if any extra's added to some old games and found some of the games (I owned Disc version's) are now apparently free
Crackdown (Xbox 360)
https://marketplace.xbox.com/en-ie/Product/Crackdown/66acd000-77fe-1000-9115-d8024d5307dc?noSplash=1
Crackdown 2 (Xbox 360)
https://marketplace.xbox.com/en-IE/...acd000-77fe-1000-9115-d8024d5308bc?noSplash=1