PDANet For iPhone

has been the best tethering software for Windows Mobile phones and Palm OS phones. It is now ported to iPhone and Android! The latest version turns your iPhone (any version) into a true WiFi HotSpot so that you can connect from your computer (MAC or PC) or iPads. This allows your laptop to go online wirelessly through the 2G/3G/4G network on the iPhone. It also supports USB tethering for both Mac and Windows users. PdaNet provides the fastest connection speed possible from your data service and data signal.Update 10/15/2011 - If you have updated your phone to iOS 5 or iTunes to 10.5, please update PdaNet to 5.30 from Cydia. If you use USB mode please also update desktop client to 5.30 from here. Follow all PdaNet updates at twitter.

How to Install - version 5.30 Apple has not accepted PdaNet into the App Store due to understandable reason. You will need to jailbreak your iPhone and install it through Cydia. To use WiFi mode you do not need anything installed on the computer end. To use USB mode, download the desktop client on Mac or Windows.