|NOTE: This is particulary trivial for the Debian distribution.|
Twinkle is a Voice over IP ( VoIP ) application. Its purpose is to make phone calls via the Internet, instead of using the telephony network. Here is a way to get the command line twinkle working on Debian.
apt-get install twinkle
It will install some dependencies (about 83.0 Mo for me) but after Twinkle have the advantage to be quite ergonomic and lightweight!(about 15Mo in memory)