A few months ago I have discovered Peakclick.
I was very skeptical, because almost all PPC programs I tried before were not even making 30% of adsense. Once you login, one of the first thing you notice on Peakclick is the top webmaster section where you see that some guys are making $2000/day with the program. So you say "yes, it is possible" and give program a try. First you don't make so much, since after you join you have the "Not Approved" flag which prevents you from getting all ads. However, in a few weeks you get approved and income starts to raise.
Another good thing about program is that you get paid twice a month, even more often if you make requests and many payment methods are supported such as: Epassporte, wire transfers, Webmoney, Western Union, check by mail, Fethard.
In my opinion this is the second program after adsense that you should use(I didn't check YPN yet).