On the state of IP-Telephony
It has been some time since I last posted about IP telephony. Many things have changed, Skype is widely used (even normal devices support the protocol now in hardware, making nice things like mobile-phone-like gadgets that can use public hotspots possible).
I ranted a lot about VoipBuster and similar offers, but it seems my fears were unfounded. Voipbuster now offers free landline calls to Austria and Switzerland, and cheap (1cent/min) to Germany not to mention free landline calls to exotic countries (Guam, Estonia, Iceland, USA (+mobile!)) and SMS text messaging.
Gizmo Project is another provider, and they now offer free (5min/day or 10 if you register) calls via a normal browser (plugin required).
edit: I forgot to mention Jajah. I had heard a report about this company some time ago. They also offer free or cheap calls, but you only have to enter the numbers into the webform, and they call you and the recipient and connect you. The special thing about this company is that it was founded by two Austrians!