The Locked ON Proximity Sensing T-Shirt probably won’t help you avoid those awkward run ins with the X, or worst case help you maintain the appropriate proximity according to the restraining order. But it most certainly will help you find the perfect geek partner. Step within 5 meters of someone wearing the same t-shirt and the shirts active display, which runs of 3 AAA batteries “for hours”, will go from ‘scan mode’ to ‘lock on’ mode. Thinkgeek has them for $20 a pop.
Animated version after the ‘leap’