I had the same problems with alladvantage slowing the machine down to nothing, but a week or so ago they released a new version which has made it much better (I think it's 1.3 or something)

You have to activly move the mouse around for it to earn cash, when the logo's head goes red you have stopped earning. I don't know how long before moves, but it's not as long as some of the other cash to surf places.

They are however, the only place I have found that is sending out checks on a regular basis, I now count it as a bit of extra money at the end of each month. If you do sign up please use me as the reffer:
http://alladvantage.com/home.asp?refid=dzz738

Mike