http://sys.us.shuttle.com/Models.aspx
get a shuttle XPC.....Good looking and small, you can get one on their site or just spec one out yourself.
I think the I series or the G series will fit your needs ($900-1900)
I got the shuttle case (comes with motherboard) on some other site.
Shuttles motherboards kicks Azz
I had mines for 3+ years (I'm a Gamer)
Shuttle XPC SB75S
Intel P4 2.66
1 gig Corsair with heatsinkers
audigy 2 sound
Nvidia GF4 128mb video