Hand reading 101: Most common & exploitable reads?

[ChipStorm]

All you expert hand-readers out there:

What do you guys see as the most common villain tendencies that make you money, and how do you pick them out? (Ya, I know, you see them do it. Anything more?) Care to share some specific examples?

In my extremely limited experience in actually attempting to read villains, what I've seen so far is players who:

* Play any 2 sooted
* Overplay their top pair
* Seem to bluff a lot (although without a big sample size, how do you tell?)

And I think I've seen guys who float but give up on a second barrel, but now I'm not sure if I'm imagining things. Do you ever go wrong on your reads? How do you check yourself?