Wow, I just went through my system looking for 32-bit software, and discovered the nearly all of my games are going to stop working come next month. Fortunately most are available on Windows via Steam/GOG, so I'm installing things there.
Most are older, so performance isn't an issue, though I do have to down-res the graphics a lot.
The one thing I've noticed in the past is that gamma control doesn't work. Games like Dragon Age:Origins are far too dark to actually play. Does anyone have a workaround for that?