Amazon and Newegg both have the Rosewill Legacy U2-B window for $70.
The U2-B is is relabel of Jonsbo's U2-B cases. They are very small aluminum mini-ITX cases with the classic IBM PSU-at-the-top where the PSU helps draw hot air out the top.
Because of less volume and frankly lack of room it's not a good case for top-end systems.
The reason I like it is it's small and its air design is good.
Jonsbo also mfrs the V-series cases such as V3, which use thinner aluminum and have a design that's not very good.
I also noticed the Rosewill W1, a combination steel/alu case that's much bigger and I think it's designed well (motherboard upright, PSU underneath, lots of room).