Cool iPhone/touch Apps, what do you like?

Forgot that using 3g for data would probably incur data roaming charges, not sure how that works out of the country.

As far as I know, skype iphone app has always worked over wifi, but whether there are charges or not I don't know.

I don't use it, I use ICall, which is free. One of my brothers lives in the mountains and I get no cell service at their house, so I just use Icall if I need to make an outgoing call over their Wifi network.

ICall lets you use Wifi to make voip calls, but not to a computer directly to a house phone or cell phone. much better than having to talk to somebody sitting at a computer. Downside is the calls are limited to 5 minutes I think, but you can call right back if you go over that so really not an issue for me.