This guide will let you share your internet connection by Bluetooth
so that you can surf the net on your bed without paying high GPRS/HSDPA rates.

Im just summarizing the steps, credits goes to the author of websites at the end of this post

My setup:
Nokia n73 (most Symbian phones will do, even Sony Ericsson's)
Feisty i386 (just about any distro will do)
bluetooth dongle supported by Ubuntu (