I'm currently using a RAIDMax Smilodon, which is a pretty decent case you can get for under 100$. Doesn't look half bad too, if you're into that.
Comes in Green or Blue lights (though I'm sure you can get others if you want):http://www.newegg.com/Product/Product.aspx?Item=N82E16811156078http://www.newegg.com/Product/Product.aspx?Item=N82E16811156063
Four Fans as well:
120mm intake fan in the front
120mm exhaust fan in the back
80mm side intake (it blows air over the GPU, very nice)
80mm side exhaust fan (over the CPU)
Both side panels open, which makes it a breeze for motherboard install.