We managed to save a lot of cash switching our phone lines to PennyTel VoIP.

They have great call rates (At the time of writing: 8c AUD flat rate local calls, 5c SMS and 10.5c per min AU mobiles), good tech support and their members area is easy to use (after a couple minutes exploration).

We set this up by registering for a free account on their website (www.pennytel.com) and pre-paying for some calls.  We use the free X-Lite softphone on Windows XP* to make the actual calls (PennyTel offer a PDF with setup instructions for X-Lite.  Very easy & straightforward setup).  You will also need an USB phone or microphone headset as well.

There are still a few restrictions though with PennyTel though: there is no API for sending SMS from a remote system and they do not allow transfer of 1300 numbers.  Although i found this to be a bit of a restriction, these factors won’t be an issue for most people.

Cheap call rates, ease of use, good support.  Enough said i think.

The Links:

Free X-Lite Softphone (it is free, none of that free download for 30 days trial crap) - http://www.counterpath.net/x-lite.html&active=4

PennyTel - http://www.pennytel.com

Cheap Headsets - Umart (http://www.umart.com.au) or Ebay (http://www.ebay.com.au)

User Support & Info Forum - WhirlPool Forums (http://forums.whirlpool.net.au/forum-threads.cfm?f=107)

* X-Lite software also available in Linux, Windows and Mac Versions.