Hey guys, after discovering Microsoft Portrait (video/VoIP conferencing app) I started looking into using my Axim as a way to talk to friends and family on the computer. Then I start finding a few clients that support calling phone-lines off your PPC. At that point I went nuts.
Personally I think everyone should check this out:
Stanaphone
Basically its a service that uses this SIphone PPC client to make calls over the internet to land lines. You can configure the crap out of the software as far as compression settings etc goes and its skinnable. Plus you can sign up with this company without providing any credit card info and they give you 10 cents to try the service out.
I didn't think it would work but there I was using my Axim as a cell phone at my house. I live in Canada so it's 2 cents/minute within Canada/US, so that's 5 free minutes to call around and check quality. I found the Axim to work well as a cellphone, even just setting the speaker to middle volume the speaker on the other end was clearly audible.
Skype is another good client for this sort of thing but Stanaphone's pay system is better I find (can be set up to automatically add cash to your account if you run out) and lets you put money on in $5 and higher increments whereas Skype is $15.
Bottom line there's no committment, no connection/disconnection fees, and they give you an american number that works just like a cellphone with unlimited incoming calls. I'm really happy with this service as its cheaper than any long distance and requires little to no committment on my part.
Post your own thoughts on clients you've looked at.. for video conferencing Microsoft Portrait is a great piece of software as well.. it integrates with messenger to boot.