ID..Mite or tick?

[Viking Dr]

I saw on my glass a bug of some sort. It was roundish in shape. It had 2 legs out the front and 4 out the back. Or the other way around. It was small. I mean tiny. The point of a pin. I was looking at hydroid Medusa with a magnifying glass and saw this thing. It was much smaller than the Medusa, a lot smaller. Any Ideas? No way to get a pic. Too small!

 

[Zappo]

Check out this site in the zooplankton section for some pics that you can compare it to:

http://www.chucksaddiction.com/hitchhikers.html

It's probably some sort of copepod or isopod.