In anticipation of my Panasonic L10 being converted for infrared, I picked up a Litepanels MiniPlus IR light, and although I still don't have my camera, I started messing around with the light and my iPhone today. My Panasonic GF-1 isn't very IR light sensitive, but it turns out the iPhone 4 is.
Here's how the light looks through the iPhone:
The really cool thing about this light is that when its on you can't see it with the naked eye. For comparison here's a shot of the iPhone from the GF-1:
You can clearly see how brilliant it is to the iPhone and invisible to the GF-1; its also how it looks to the eye. A full spectrum conversion should be much more sensitive, the IR light only reaches about 1 foot for the iPhone. Here's a nice iPhone-monster-light-infrared-self-portrait, that's the light in the foreground: