Free Edition
This app only works with phones that have root/super user access (e.g. the Development Phone). This app tethers your cell phone's Wifi internet connection to your PC. The connection between your phone and PC is a bluetooth PAN connection. Please visit http://www.androidactivity.com/tetherBlu.html before installing!
This is the Free version which will only work if you have a wifi internet connection on your phone. If you want to tether the cell internet connection try the Premium version.

Free Facebook Chat / Facebook Messenger! Chat for free with all your Facebook friends with BeejiveIM for Facebook Chat! Free!

Free messages, Free Calls. Unlimited!
Nimbuzz Messenger combines the power of internet and smart phone messenger into one, and lets you make cheap international voice calls, send unlimited chat messages, share files on any mobile device across popular messengers. Nimbuzz Messenger is available on Android, iOS, Blackberry, Symbian, Java, Windows and Mac.