A couple notes on this horrible idea (yes I run a couple ad networks).<p>1) Giving up 50% of their revenue to charity isn't that impressive considering if they actually paid the publishers whose content they are running their ads on they would most likely be paying 50% or more. This is like if Robin Hood kept half of the stuff he stole, wouldn't seem so noble.<p>2) You are essentially opting in to see these ads. Sure you might be a good target market since you wanted to see the ads, but chances are it's going to be a small and quickly saturated audience. Advertisers will most likely see a quick drop-off in results.<p>A much more interesting implementation would be one that continues to show normal ads (through ad networks, etc) but takes the revenue from them and gives them to charity. You could even hijack affiliate links as well and donate that to charity. I always thought it would be super evil, but interesting, for someone like Bing to sell a toolbar that displayed their own PPC ads on Google's search results and paid some of it back to the user or charity.