Dell Dimension E510 (Pentium 4 630 3GHz, 512MB RAM, 80GB HDD, XP Media Center 2005)

Pros: Good for gaming, multi-tasking, very quiet, and have you seen the price?

Cons: No Dual-core option

Summary: Originally I was planning to get an XPS 600, however, when I tried my friend's XPS, I found it to be way too loud. So I went ahead and bought the E510. First off, here is what I customized it with: 3.2Ghz P4 processor, 1GB DDR2 RAM, Windows Media Center OS, FREE upgrade to 19 in. flat panel, ATI 256MB graphics card, 160GB hard drive, Sound Blaster Audigy sound card, and the Dell 2.1 speakers...all for the low price of $828.80!(with 30% off coupon I found on Google)The performance is top-notch in both graphics and other multi-media apps. I was amazed at how remarkably quiet the BTX system was and the fact that it ran Half-Life 2 at a solid framerate.
Th processor is very fast, but it leaves me craving a dual-core processor option. The 1Gb of RAM is all I need, however, there is room to expand upto 4GB in the future. It's not not by any chance an XPS, but you cannot beat the price of this incredible Entertainment PC. I would rate it a 10, but the lack of a dual-core option lowers it down to a 9.
Happy Holidays!