Any good suggestions on a good looking case with a window, for under 140 $
The fractal design define r4
The fractal define R4 with a window is practically the only windowed case in your price range that won't make you puke unless you go slightly above it and get a Corsiar 650D.
I've been thinking of the NZXT phantom 410
How important is the window really? You will be able to get a number of cases that perform VERY nicely in that price range if you can live without a window.
Personally, I spend the majority of my PC time looking at the monitor rather than my case.
Bitfenix Raider Windowed. It doesn't support much liquid cooling, but it is very attractive (in my opinion) and it has lots of peripheral connections on the top, which is where many people want them. Of course I don't really care if it has a side window or not, because I can always break out a straight-edge, a sharpie and something cylindrical and use a drill and a jig-saw to poke a hole in the side of my case and mount a window. You can add a window to just about any case for around $40 for the acrylic and whatever bits you need, as well as some tape. Do realize though, that if you aren't extremely careful, you will usually wind up ruining the paint by it heating up and discoloring. So be ready to sand and paint the case as well. But a jig-saw is much easier than a dremel for this.
Corsair C70 (on sale),
I really would like a window, as i often go to LAN partys, and after the summer i'm going on a school where i basiclly live and i wanna show of my parts. Though, mobility is not a problem for me, i don't need a handle or something like that.