Mobiluck, an interesting location-based application which offers the following services:

Send messages for free and meet people with your mobile phone, Today, with MobiLuck you can already: Detect all nearby Bluetooth devices. Your cell phone rings or vibrates when it finds one. Send messages and photos for free to friends or strangers with no need of their phone numbers. Hear when you receive a Bluetooth message and reply to the sender! Send your profile and receive profiles from other MobiLuckers including their photo.

Their agenda is also compelling:

Play multi-users games, download ringtones, logos, music and games. Meet people, recognize friends of friends and share your passions. Attend professional exhibitions, exchange business cards and find new customers. Find a job, an apartment, a second-hand car, a pub, an unoccupied cab, win miles and do some shopping. Save time in public transportations and lines, enjoy cities and museums… and many other things…

In the description there is this "You're surrounded by great people who are open to new experiences like you! At this point, if you're not too shy, you can contact other MobiLuckers who are having fun with their devices by using their screen name to call them: "Is that you, Bulldozer?"". It's a bit strange to assumed that having a bluetooth phone activated makes you willing to have 'new experience' (it can be activate right from the beginning) but...