I've ordered mine! A full breakdown of what I ordered:
HP ProLiant MicroServer -
£121.15 (after cashback)
2 x Kingston ValueRAM memory - 4 GB -
£31.46HDE Wireless USB PC Remote Control Mouse for PC (Chinavision CVSB-983)
£7.95HIS HD 6450 Silence Edition
£36.99I went with 8Gb of RAM because it was so cheap. Might as well have too much.
The remote is just for the IR receiver so I can use my Harmony remote to control it, I've read that that remote is supported in the Harmony database.
The 6450 seemed to be the highest performing passive, low profile card I could find.
I'm holding off adding any additional drives because I'm not short of storage at the moment. My DNS323 is still doing a good job for now but I expect it will be turned into a full 'dumb' backup device once the HP is up and running.
EDIT: Delievered! Let the fun begin!
EDIT: The remote linked I havent yet managed to get setup properly and the receiver has a terrible range, I dont recommend it.