WTF are your programs putting in appdata? It's a local cache. Yes, I agree you should be able to move the local cache, but that is the thing about local caches: programs expect to find the local cache in the place they left it.
Anyway, joking aside, if your local cache is too big, it's probably (1) Outlook local email cache or (2) Crash dumps. Delete the crash dumps, and move the mail cache to a different drive.
Biting the hand that feeds IT
