Here is an App idea from Howard R.  Using the regular sightings and twitter posts of celebrities create an iPhone app that tells you what direction and how far it is to the celebrities on your list from where you are right now.

Where is Kim Kardashian?

Where is President Obama?

Where is Anthony Weiner?

Where is Rush Limbaugh?

You get the idea.  The technology exists.  All you have to do is put it together and start to rake in the money.  People want to know this stuff.