I just came up with this for a competitor's forum, so the pricing might be slightly off and there might be slightly cheaper components over here... the basics are the same though.
Basic DVDRW
CoolerMaster 334
AMD Athlon 64 X2 5200+ (2.7gHz AM2)
Biostar MCP6P M2+ (AM2+)
(Competitor own brand) 2gb PC2-6400 (single stick)
Xilence 420W gaming PSU
160GB Hitachi CinemaStar (SATA-2, 7200RPM)
PowerColor ATI Radeon HD4650 512MB
Total cost including VAT is a smidgen over £245 and it'll quite happily run Call of Duty 4, Counter Strike: Source and that generation of games no problems. It'll even manage crysis on 25-30fps on medium at 1440x900 (based on similar rigs at the time of release).
Personally I think it's not a bad rig for less than most netbooks...