This is my lowend system:
AMD Athlon XP 2100+
Mainboard: Acorp VIA KT600
Ram: 256 Mb DDR333 CL2.5
Video: ATi Radeon 9200 128Mb
HDD: Seagate Barracuda ATA100 7200rpm; 40Gb
Monitor: Nokia Multigraph 446Xpro 19"!
Other useless stuff:

LG 52x CDROM
Philips Stereo Speakers
A4tech Keyboard
Mitsumi Wheel Mouse
Edit: Everyone seems to be posting their dream machine! Here's mine:
AMD Athlon FX53
Mainboard: ASUS or ABIT "full-option deluxe special edition something"
Ram: LOTS AND LOTS! maybe 2-3Gb
HDD: A 300Gb SCSI monster or at least SATA
Video: ATi FireGL
Monitor: 21" TFT
Everythind else are just accesories on this baby!

The one and only!
--Opty165@~2700Mhz@Xigmatek S1283--DFI LanParty Expert--2x1GB DDR500--Sapphire HD3870 stock--2x160GB Hitachi Deskstar SATA2 Raid0--LG DVD-RW--Corsair 520HX--Antec 900 moded--Dell Ultrasharp 2005FPW @1680x1050@60Hz--Wacom Intuos 2 A4 Tablet--
No more room for the rest of them...