yes but only for useful answers :)
No, I haven't, but someone had thanked me for requesting him, which I hadn't. I read his profile and thought wow this is my kind of friend, (caring, kindhearted, & a non perv), so I requested him and we have been good buddies since.
Yep, I figure they didn't understand how it'll automatically choose "best answer", at the start of a new day.
but it was to them... free stuff rocks.