We're seldom impressed with LED flashes on cellphones, but it's arguably better to have one and use it sparingly than not have one at all. That's why we can understand Ryan's frustrating with his iPhone 3G: he decided to mod his Mophie Juice Pack to add an LED flash
The button was taken from a simple flashlight, while the rubber cover was donated from a laser pointer. The LED itself, meanwhile, was a low-profile 5,550 mcd piece that cost $0.59. As for the Juice Pack, once reassembled it all works as it did before, with the battery now also used to power the flash.
You can see an example photo in the gallery below; original on the left, and the version taken with the flash powered on on the right. If you get the right distance - not too close to saturate, not too far away so as to make it pointless - then the LED can obviously make a difference. Ryan's second-gen mod will move the trigger button to a more ergonomic place.