I can get a new copy from ebay for less than a fiver but I think my PC will farts it's bowels out if I even show it the packaging.

What's the minimum spec?

Aftermath is not that tough to run:

The minimum requirements are:
Windows 98/2000/XP
Pentium III 500 MHz
128 MB RAM
GeForce 2 MX video card with minimum 32 MB onboard RAM
8x speed CD-ROM
DirectX certified sound card
1.25 GB free HD space

Suggested system for optimum performance is:
Pentium III 1 GHz
256 MB RAM
GeForce 3 with 64 MB onboard RAM

Aftershock on the other hand is a little tougher:
Minimum Requirements
Operating system: MS Windows XP / 2000
Processor: Intel Pentium III or AMD Athlon 1GHz
Memory: 512MB RAM
Video card: nVidia GeForce 5700 or ATI Radeon 9500
Sound card: MS DirectX 9.0 compatible sound card
Hard disc: 4GB hard disk space
CD ROM: DVD ROM
Other: MS DirectX® 9.0c

Recommended Requirements:
Operating system: MS Windows XP
Processor: Intel Pentium IV or AMD Athlon @GHz
Memory: 768MB RAM
Video card: nVidia GeForce 6600 or ATI Radeon 9700 PRO

I think Aftershock is a much better game, but Aftermath is also interesting.

Gulp! I suppose I should be able to run Aftermath but you just know when they give ideal stats they mean, "Try and run it on less and your chip will explode and be fired out the fan apperture." Well, what the hell, it's only a fiver.