Online Tells & Techniques?

Playing online poker for fun after a few years away.

Saw a mention of “online tells” in a thread and wondering what they are for all of you.

So far I have in mind:
HUDs / note keeping & general player pattern observation
Time lapse (or lack of) for player action

And what types of things do you do specifically while playing online to adjust players' perception of you?
Do you hesitate using the "auto check/fold" option to control your reaction time more specifically?
Do you say things in chat that make people think you're crazy?

I try to keep track of super aggressive players and really weak players...i use bovada so other than that theres not much i can do but if u play at acr its def alot easier