I hate them. And love them. I love them 'cause they're great brainteasers. I hate them when there's a problem I cannot solve. Like this one:
http://www.iqtest.dk/ Generally pretty much straightforward, but what the heck is the solution to the last question? I know I won't get into bed again 'til way past midnight, trying to solve it.
I hate them. Yeah, I have great scores, but they steal my time!