Unison has developed a free unified communications suite built on Linux. The suite, which includes VoIP telephone capabilities, email, and instant messaging, is affectionately named “Unison”. The Beta version is available for free now. There is a Windows client application. While the server portion of the product runs on Linux, there is oddly no client available yet for Linux. For small to medium enterprises looking to jump on the unified communication bandwagon, a free tool built on Linux with a Windows client application might be a great way to test the water. You can learn more about the suite from Unison by reading this PC World article.