Yes it can make calls/SMS and everything a normal phone can do. It is a phone that runs on a debian derivative

The Nokia N8 and the Nokia N810 have Micro-USB A connectors and yes they have USB OTG

I have to agree with rxmd, the nokia N-series and the E-series have a an amazing sip stack. one more thing, sip has a lot of issues behind a NAT.one more opting is the nokia n900, it has a front facing webcam and has complete Skype integration.