New Scientist 21 February 2004 P 21 "Chips to ease Microsoft's big securtity nightmare"

It seems that intel & amd are about to release the latest version of their processors which, coupled with a new version of Windows XP, will prevent buffer overflows.

... chip makers Advance Micro Devices (AMD) and Intel are developing processor chips that will deal with the [buffer overflow] problem. AMD's Athlon-64 (for PCs) and Opteron (for servers) will protect against buffer overflows when used with a new version of Windows XP.
The new chips/XP work by identifying memory as either executable code or data and prevent data from overwriting code and code jumping to execute data.

A very good idea IMO

Steve