This app called HandyLight appears to be a normal flashlight app, complete with multiple colors. It has a hidden feature, however - it also allows you to wirelessly tether your iPhone, of any model or firmware with or without a jailbreak, to your computer, iPad, iPod, or anything with ad-hoc wifi.

[youtube]http://www.youtube.com/watch?v=CFdav6Lw1Is[/youtube]
Note: Apple has removed this app from the App Store
[Via]
<a href="http://dailyiphoneblog.com/2010/07/22/iphone-tethering-without-jailbreak-using-the-flashlight-app/">

[Read the original blog post]
</a>