Looking to buy small used filter/skimmer

Hi everyone, my name is Clayton I am new here.
I have had a 75 gal. marine tank for a few years at home. Now I am in college and am looking to setup a 10 gal. nano tank in my room. Since I am a poor college kid, I am looking to buy a good used filter for a 10 gal. marine tank. If you have a small filter/powerhead that is good for SW, and a 10 gal. tank sitting around let me know. I would like to find one for somewhere under $20. Also is a skimmer necessary for a small 10 gal. nano? I have heard lots of bad things about skilters. Thanks for everyones help. Clayton, aka. Coolclay

Thanks thats what I thought. Now I just need to find a cheap filter.

Come on, someone has to have an old filter sitting around, that they can sell for a some quick cash.

Yea thats what I am checking now, Penguins, and Rios are pretty good filters right? I found a good deal on a penguin 125, now I just have to wait for the darn auction to close. That's why I'd rather find one here. Oh well, thanks anyway.