I use SafariBlock to block pagead2.googlesyndicaton.com, so no. I wouldn't click on them anyway. Only times I've EVER clicked on ads is when they were hand-picked by the site they were displayed on.
If you're talking about the adaptive google-analytics ads, I *cough* do haterblock them. Before I started doing that, I have to say, they seem to come up with ridiculous nonsense. If they were linking me to Amazon.com or Body Shop or Ralph Lauren, or some other store I'd actually buy from, fine. But they seem to mostly link to weird spammers.
No, and I hate when they're on people's personal websites and they just mess up the layout. On bigger sites it's not as bad. I still never click on them though.
Rarely, but if it looks weird or interesting, I do click. I'm on broadband so it only takes a few seconds to see where it goes, then back to normal browsing I go. What the hell.