I like the idea a lot. I worked at a larger company who offered a consumer service like this for a while. We found that most consumers really didn't convert well for the service and we had to pump in lots of marketing to get results. The most popular categories were 'psychics' and 'health'. Basically people who had STDs and were embarrassed and people who wanted their fortunes told. That said, there was a non-trivial amount of cash in those topics...

edit- I forgot programming. That was a big category as students often wanted their homework done for them...