google's AdSense
 

Does the site earn money every time i click on a Google ad? or is it only if they purchase something from the Google site?

I was just wondering, because - Hey! if you get paid per click then I'll start click on them (open in new window & hide it) more often to help support the site.

Adsense is largely a cost per click thing, but seeing as how it's against the terms of service to have users clicking ads they're not interested in, I wouldn't encourage you to do it unless you'd click on it anyway.

:D Terms and conditions noted. You will not ENCOURAGE me to participate in your Pay Per Click adds.

Well, I'm not even pretending to not encourage you, I actually (ethically) wouldn't do that, :p