Brightkite is a location-based social network. In real time you can see where your friends are and what they’re up to. Depending on your privacy settings you can also meet others nearby. Brightkite also allows you to post photos and notes at locations for others to see.
BrightKite is now available in version Alpha 0.1.2.
Download BrightKite OTA (Requires OS 4.5 or greater).
Download BrightKite for your desktop (Required IE and Blackberry OS 4.5 or greater).
[Thanks for the tip @LouTreize]
