I've seen a smattering of it in the past, but this year, the existence of services like cramster.com et al. really hit my upper-level courses in force. Seems they have pretty thorough coverage of most popular texts. (Even for books that aren't available at cramster, a quick google search turned up downloads of the solutions manuals for every single quantum mechanics text I'm contemplating using next Fall.)
I've always rewarded homework pretty heavily because doing it is where most of the real learning comes from in junior and senior level mechanics, qm etc. I am loathe to change this approach. I am, however, being forced to consider alternatives.
It's a bummer. Either I go to writing all the problems myself (maybe not a bad idea in principle, but a MASSIVE time sink), or to choosing books just for their obscurity, or to devaluing homework and just giving a bunch of tests. The latter doesn't really seem much of an option .. I don't generally find students will do anything that isn't actually required, no matter how much they "ought" to. They just wait until the tests to realize they don't understand how to do it.
Anyway ... as I contemplate what I'm going to be doing with my quantum course in the Fall, how are the rest of you coping with cramster.com and the rest?