Do free WIFI hotspots exist in Amsterdam?

http://www.hotspotamsterdam.com/FlashMain.htm this is good if you don't mind paying.

I like to hang at the Dolphin's Coffeeshop-- they have free wifi--
(but no a/c to plug in my laptop-- so make sure you have a full battery!)

The guy in the Dolphins told me the last time I was there they were offering WIFI free, shame they don't have anywhere to plug into, my max battery life is 2 hours. Is it as simple as powering up the laptop and switching the WIFI sniffer on?

Quite interested in the link that was given as well, doesn't seem terribly expensive for wireless broadband anywhere in Amsterdam. Has anyone tried this service and what did you think of it?

Does anyone know of any other places such as the Dolphins offering WIFI?

Dave