Second Monitor

I'm looking into getting a second monitor for my 21.5" iMac. I decidedly am not interested in paying for Apple's thunderbolt display. I was wondering if anyone had any suggestions for a monitor in that size range that would go at least moderately well (aesthetically speaking) with the iMac. It doesn't have to be perfect, and I realize it won't be, but a black plastic piece of crap would not be desirable. I'd like 1080p, obviously.

Has anyone else been in the same boat? Does anyone have any ideas or any suggestions?