First off, thanks to Ian for taking the time and effort to post all the step by step guides! I wasn't aware of the media capabilities until I found this site, so now I have alot of new toys to play with!
Like some of the others here, I'm an old DOS-jockey, starting out on an IBM XT with 28kb of RAM and a single sided, 5 1/4" floppy booting from IBM DOS 1.2!! I still have, on the bookshelf, a copy of MS DOS 5.0, on 5 1/4" floppies, complete with license and manual, and still sealed in the original shrinkwrap!
I have been in the IT world for a good many years, and have worked with Plessey proprietary OS, IBM System 36, Unix, all the flavours of Windows, Warp 2, Sun OS (I have my own Sparc station sitting on the shelf gathering dust), telephone switchgear including GTD5 and Lucent's 5ESS and 5E and more recently with a Unisys 450 and a 750. I got stuck into Linux about 6-7 years ago, and started with Linux From Scratch (build your own distro) which really helped me understand it a lot better!
I just upgraded my desktop, so the old desktop became my new server. The old desktop was originally an HP, but all that remains of the HP stuff is the case. The PSU is a 500w Thermaltake, the motherboard is an ASUS (forget the model offhand) sporting a twin core AMD 4200 processor and 4 gigs of RAM. I pulled the NVidia 8900GT video card for another project, leaving just the onboard video, and also tossed the modem and front USB/media ports for more drive space.
Running Ubuntu server 13.10, the current boot drive is a 156G Seagate IDE, 56g as system and the rest as a "data" drive for shared space (for now). I have more drives to add to it yet including 4 300 gig ultra SCSI drives (15,000rpm! Oh yes!) as soon as I rescue my PCIe controller from another machine. Another reason the video card got tossed, only one PCIe slot on the mom board! I also have a couple of 500g SATA drives lying around, some with old data on, so I can upload those to the SCSI array, then wipe them and raid them together in a secondary group since the momboard does support raid 5 on the SATA ports.
The new desktop is running 14.04 and is an 8 core AMD with 16gigs of RAM, boots from a 128g SSD and a 500g SATA mounted to /home. That should keep me going for a while! I have a dedicated firewall/DHCP box, in an old blade server, 1g RAM, pentium something or another processor and an 80gig hard drive running on FreeBSD
I had the server all set up and running, shares working (no Samba, the only windows in the house have curtains on them!) and a whole bunch of add-ons from the media server project installed, but then I hit the "virtual machine" section, so I blew it all away and started over! Ram is really the issue for multiple VMs, and the motherboard is maxed out at 4 gigs, so I may invest in another, smaller SSD for the OS and swap files.
Another mini-server project I have in mind:- I have a lot of PC type DVD players lying around, so I may string them together in a single box as a back end server to the main server so I can have half a dozen movies loaded ready to stream, or ready to rip to the main drive arrays, at any time. This would also give me a second dedicated file server, where I can remove DVD drives and replace them with hard drives over time, almost treating it as an intelligent NAS.
My home network, such as it is, is mostly hard wired cat 6. I do my own wiring, so I have cable and connectors where I want them, and can quickly add a new drop if I need it since every drop I've pulled has at least one spare cable behind it. The whole thing hangs off a 24 port managed Cisco switch, and includes a Cisco/Linksys wifi router. The edge router is an ISP provided cable modem, giving 25mb down and 8mb up (approx) but routes nothing since my firewall is in the DMZ and handles the real traffic.
You did ask for specs!

Davey