It' 9:55AM and I'm sitting in Windows XP SP2 War; there's a little debate going on which has nothing to do with security, so I thought I'd write this :)
As you may be aware Windows XP SP2 will support “No Execute” or “NX”, which can mark memory as, well you guessed it, no execute. What this means is if a bad guy can get code onto the stack or heap through a buffer overrun, he can't get the code to run. Note, this is not a replacement for good - it's just goo ol' defense in depth. Which is goodness.
Right now the AMD Opteron and Athlon 64 (in 32-bit mode too) support NX. Intel's upcoming “Precott” will support it. And now, Transmeta has announced support too in their TM8000 “Efficeon” chips, which should be available mid-2004.
This is goodness.
You can read their announcement at http://investor.transmeta.com/ReleaseDetail.cfm?ReleaseID=135307.