I'm sure most of you will agree that you never really finish your shack! It's always a work in progress with changes and / or additions. I recently acquired an HP-DC7800 USFF pc. At first I thought it would be a fun project just for the sake of having one and keeping busy.Well, to my surprise, I loved it, so much, that I bought a second one and they replaced both of my towers in the shack! These mini pcs run so quiet, you almost forget they're on at times.I got the idea from seeing one at my doctors office and seeing how quiet it was. They measure about 10"X10" square and about 3" tall. They run on laptop HD and laptop ram. This was great for me because I had a few spare drives laying around. They are core 2 duo machines. They were initially 2.33 Ghz. clock speed. I upgraded them to 3.0 Ghz for a whopping $20 on ebay. Easy as pie to do too.Both have 4 gigs of ram installed.I have a volume license for Windows 7 so I was not picky what OS they came with, I use 1 for all my programming needs and the second one for anything and everything! Total invested on both was @ $150 shipped.The shack has so much more room right now, it's amazing! For running the shack which includes about 12 different radios, it is more than enough. Just passing this along in case any of you need to save on space like I did! Cant say enough good things about these mini PCs.