At this time, my system consists of:

ECS K7S5A motherboard (SiS735 chipset max 266FSB - max CPU Athlon XP2600+)
AMD Athlon XP1600+ CPU
512MB PC2100(?) DDR RAM (266MHz)
40GB IBM 5400RPM hard drive
Turtle Beach Montega A3DXstream sound card
US Robotics 56K external modem (firmware upgrade to V.92)
16X DVD drive
16/12/40 CDRW drive
GeForce 3 Ti200 video card w/128MB DDR RAM
Envision En770 17" flat CRT monitor
Win XP Pro + SP1

The XP2400+ is already ordered from NewEgg and on its way (so I'm kind of committed to that upgrade).
Maybe down the road I can pick up a better sound card and/or a GeForce FX5200 Ultra (based on the 5900 core) and be set for a couple of years.

I'm actually pretty happy with the system, it should hold me (with occaisional minor upgrading) till the Athlon64 is ready for primetime.
My last system before this was a Socket 7 K62-550 (presently being prepared for Linux experimentation). I tend to make pretty big jumps in technology from system to system.

As I said, I'm sticking with what I've got and making the best of it.