i have been building rigs for freinds and family and myself fo several years now. i find it hard to understand enyone going out and buying a rig ready made when for less than half the price you can build one yourself. my current rig is;
quadcore 3ghz
nvidia gtx295 video card
1000 watt psu
asus p5q-e motherboard
4 gigs ram @ 1066hz
win7
48x duel layer dvd
1terabyte hitachi hd for storage @7200rpm
300gb western digital velicio raptor hd @10000rpm
x-fi platinum sc
about £1,700 to build
dell do one similar for £3,500! see what i mean.