Signs a shy guy likes you?

As most people learn to recognize over time is that there are certain physical tell-tale signs that someone finds you attractive. Now in some subcultures these are called IOI's, or Indicators of Interest. Now there is an almost unending list of give aways, but some basic ones are:
if every time you look him in the eyes, you make eye contact for a second then he looks away really fast.

If he is trying to qualify himself to you by telling you stories to you that he naively thinks will impress you.

Even if he doesn't try for your attention, he will subconsciously stand near in the hopes that you will address and acknowledge him.