Konftel 300IP - connects to VoIP-lines via SIP protocol. This phone is equipped with advanced features that allow making more efficient conference calls. For example, you can record and store records of meetings using the memory of SD card.
Orpheum offers its iVoice (SIP trunking) and hPBX (Hosted/Virtual PBX) services exclusively to businesses in the USA and Canada. Both services start at $25 per month.