The SMSj library allows you to send SMSes (GSM) from the Java platform. It gives you full control over the SMS including the UDH field so you can create and send EMS messages, Nokia ringtones, and images. It provides a pluggable transport layer that allows it be used with a range of different SMS servers.
VoiceBuntu (formerly Ubunterisk) is an Ubuntu-based live CD that uses Asterisk and VoiceOne to provide VoIP service without any system installation process. VoiceOne is a Web-based GUI for the Asterisk PBX. Ubunterisk can be used as a phone client as well as a PBX server. Ubunterisk can be administered either remotely or by accessing its local GUI. A capser-rw filesystem is used to store the system's data persistently.