This is kind of cool
http://www.gizmocall.comRequires install of a 1Mb plugin and uses flash.
The page states your limit is 10 minutes per day, however the timer on the plugin says 5, although I've had it count backwards too. The thing that's great about this is that you can literally call anywhere in the world. It doesn't seem to matter if its a mobile number. I tried a North Korea number. It worked. I figured hey, why stop there, let's go for the granddaddy of them all: +870 -- Inmarsat autolocate. Calling these numbers cost up to $15.00/minute on a normal phone! I put it in, and it even displays the price on the screen. In this case it was $9.80/minute. I called some ship in the Indian Ocean. It worked! I couldn't believe it. Let's see how long they keep this up for once people know you can call satellite phones for free on it...