Pretend to pick your nose and eat it, wobble around in the lane, lean over like you are about to throw up, wave your arms around and shout gibberish, and just generally give the impression that you are drunk and crazy. They will be forced to admit to themselves that they can see you and they won't want to be anywhere near you.

Let's hope there's intelligent life somewhere in space 'cause it's buggar all down here. -- Monte Python