We talk with top execs from three up-and-coming hosted companies: 8X8, Thinking Phones and Fonality. Hosted VoIP has been around for about eight years. A fairly simple concept--Centrex meets VoIP.

Fonality’s PBXtra 3.5 Professional edition appliance is based on CentOS 4.3 and Asterisk 1.2. Fonality sells two other retail versions — Standard and Call Center — and offers a free downloadable open ...