EDIT: D'oh...thought it said anything AROUND 100, not under. Disregard the below...
Your style preferences are up to you, of course, but I find Lian Li cases to be rather boring. How about Thermaltake's
Armor Jr? The black version is steel and the silver version is aluminum.
I've been considering it for a Conroe build I may end up doing in a couple of months. To me, it's a stylish case that brings a lot of features to the table for a good price. I like having a door but hate having to open and close it constantly (plus have it block airflow) - well, the Armor Jr is sort of a compromise since it has the two decorative flaps on the front. It's also got plenty of ventilation, can easily be configured for watercooling, and can be converted to BTX with the purchase of an upgrade kit.