Check out the new Zon·Me evolution. Sync with Facebook (pressing the top middle arrow button and then the FB Sync), get your friends lists, and start searching for them around you.
Just slide the bottom slider to set the search area, and press the BLUE dot button, and that's it you are set.
Add your own searching message in the right screen by pressing the top right button, or check out those who are looking for you on the left screen by pressing the top left button.
You can even define your custom searching lists at the right screen, to search a specific group of friends.
Enjoy finding your friends and getting together.