If you don't mind, can I ask what the specs of your new PC might be?
This is extremely tentative. The primary use of the machine will be to leach and seed BTs. Secondary as a gaming machine. Using a laptop for so long meant that I could only play strategy games, and I really miss FPSes. Thirdly as a media server. I have many terabytes of MP3s and crap, and I always dreamt of storing it all on a single machine where it would be available instantly.
Case:
Lian Li PC-2000A Plus II. This baby looks half-way like a Mac Pro, has 7x5.25" bays and 12x3.5" bays and has 3x120mm fans. I'd store 2 optical drives that I have lying around, a temperature monitor/fan controller (it just looks cool), and a card reader on the 5.25" bays, as well as maybe 3 HDDs on a hot swappable drive array.
Monitor:
Samsung HLT-5087S LED DLP 1080p HDTV. This is the only thing that I've got on hand already. It's got a massive screen, but is sensitive to viewing angle - a few inches too high or low and the picture dims at the corners. I'd prefer an LCD or plasma for color and viewing angle, but this strikes a good compromise (and is quite cheap for a 1080p HDTV). I'd be using this as both my monitor and primary TV. It takes HDMI and composite, but not VGA and DVI.
CPU:
Intel Core 2 Duo E6750 2.66Ghz 1333FSB. This near top of the line Core 2 Duo CPU is the Ars Technica Hot Rod suggested CPU of 8/07 and Tom's Hardware has it as the highest ranking Intel CPUs in terms of price/performance (AMD takes the cake for the top 5 though). It also scores very highly on UT2003 and several other graphics metrics.
Motherboard: Undecided. Any P35 motherboard should support the Core 2 Duo, and also allow room for upgrades to Core 2 Extreme and Quad Core. My must-haves for a mobo are lots of SATA ports (the max seems to be eight), WiFi (don't want to waste a PCI port for this, and I don't like USB Wifi solutions), and PCIex16 (since nobody makes good AGP cards anymore), and RAID 1 support for a pair of drives. My nice-to-haves are firewire (my mom's old iMac relies on a firewire external HDD), an ATA port, and dual PCIex16 (for SLI potential, someday). I don't overclock. Why RAID 1? I'm away from home many days a week and my computer will be on doing the BT thing. Since I use cheap HDDs, I'm afraid I'm gonna come home and find out that the drive housing my OS has been dead for a week and I've made no headway in downloading the complete HDTV version of Planet Earth, or whatever else is in my BT queue. So I'm planning on RAID 1'ing the drive holding my OS and core applications.
Hard drives: Any 500GB 7200RPM SATA drives, the cheapest ones listed on Pricewatch. I've got 25 IDE and SATA HDDs ranging from 200GB to 500GB storing everything from MP3s to sports to porn to photos. Right now if I want to access a file, I do a search in Where Is It (thanks to all who recommended that utility), figure out which drive it's in, and plug the drive in a USB-SATA/IDE adapter. This is inconvenient, and I'd like to consolidate the most important of those files into about 5-10 HDDs in the internal bays of the computer for easy access. To ensure long life, the drives will be turned off until I actually want to pull out a file. The computer will be on 24/7 doing the BT thing, and there's no reason to have the drives spinning all that time.
OS: I'd like to keep on using Win XP 32-bit, but if that means my performance is going to be bottlenecked to using just 3.xGB of RAM, I might upgrade to Win XP 64-bit. I'm afraid that my old apps won't work anymore though, since some of them are really old, like ACDSee 3.1 and Teleport Pro 1.41. So I might put XP 64 in another partition, and might even throw Vista in a partition just for the heck of it.
RAM: 3GB DDR2 800, no specific brand. I'm one of the types of guys who has 80 tabs open in Firefox on at once, so I need as much RAM as I can get. 3GB, probably in 2GB + 1GB sticks if I'm still using XP 32. 4GB in 2GB+2GB if I use XP 64.
PSU: 750W, no specific brand yet. It seems that a SATA HDD uses 27W of peak load power, so with 10 HDDs, I'll need well over 300W of peak load. Throw in the GPU and various other crap, and I think 600-700W should be safe.
Graphics Card: 8800GTS 640MB, no specific brand. It seems that this is the minimum I'll need to fully utilize the 1080p monitor for gaming. What hurts me is that this will cost nearly $400 - twice as much as the CPU and nearly as much as a PS3! I'm seriously thinking of getting a cheapo video card and getting a PS3. Which wouldn't look nearly as good in 1080p as a 8800GTS, but would be more useful (I could conceivably lug the PS3 around with me when I'm not at home).
Keyboard and mouse: IBM Trackpoint USB keyboard. I can't imagine using anything else.
Crazy? Absurd? Just plain dumb? Comments and suggestions most appreciated.