I asked a similar question sometime back and there were good responses: http://news.ycombinator.com/item?id=865297 http://news.ycombinator.com/item?id=865297 I

I asked a similar question sometime back and there were good responses: http://news.ycombinator.com/item?id=865297 http://news.ycombinator.com/item?id=865297 I ended up rolling FreeSwitch on a dedicated server on-site. I found it to be very extensible and reliable and I would almost always recommend it over Asterisk. Also deployed a couple Linksys SPA-3102 analog-to-IP gateway devices for existing lines - this is your best bet with faxes which transmit poorly over the public internet (unless you deal with T.38 and all that). I also use Flowroute (http://www.flowroute.com/ http://www.flowroute.com/) for all outgoing calls and for an extra incoming phone line (what's known as a DID). Their rates are reasonable and support is good, no problems so far. All extensions are using Polycom Soundpoint phones which sound great, have the best speakerphones I've heard, and are extremely customizable to boot. Although their XML config format was created by a madman :) Email me if you want more info about our setup. Alternatively, check out Phonebooth, which I believe just launched the other day. They allow you to use Polycom phones too: http://www.phonebooth.com/ http://www.phonebooth.com/ and http://news.ycombinator.com/item?id=1194615 http://news.ycombinator.com/item?id=1194615