I just came across an iPhone app treasure hunt across the USA.

It is called Lucky Jack's Treasure Hunt and according to the website they have hidden over a thousand items across the USA which you can find using their iPhone app.

There is a $5,000 Grand Prize up for grabs and the current stats indicate that only 32 items of treasure have been found and the grand prize is still out there.

If you are interested in this type of hunt you can find out more from the

Website here:
Lucky Jack's Treasure Hunt

iPhone app here:
Lucky Jack's Treasure Hunt for iPhone, iPod touch, and iPad on the iTunes App Store

Good Luck