Be carefull; these ad companies get twichy if sites start to get unusual numbers of clicks (as i think they actually pay for every click made). One site i go to lost their ad support simply becuase their ads were getting so many clicks.
So yeah, feel free to click 'em if they sound interesting, but try to avoid going OTT about it.
Also, I know google gets jumpy if there is even mention of the "suggest to your users that they click the ads",