The only issue with Google ads, though, is that most people got an ad blocker and a site that gets about 80 millions of hits per month will get about $0.10 worth of ads clicks in that period. When ticalc.org staff met up in 2009, all they could afford with 3 years of Google adsense were a couple of beers.
Also Google ads can have porn, sounds and flash banners, too. It would be even more work. If hosting officially become a problem I guess maybe we could go with a donate button, although fortunately hosting is paid until October 2011 for now.