4,000+ hits a day? It looks too good to be true. I think the idea is you leave your computer on and your browser open and this will generate clicks to your site. Not sure about the quality of the hits since people can basically be somewhere else while your site is being shown. http://www.autosurfnetwork.net/ I signed up but haven't used it yet.
That kind of traffic is either non-human or pop-under crap. You might as well stand in the middle of a high-way and sell your product. http://www.autosurfnetwork.net/ has been banned by google atleast 7 other times(under other domains). They always set up tehse doorway/cloaking pages and google gets on them for it. Don't use them.