RECON06 . A PLATFORM INDEPENDENT MULTI-CAVITY NOP VIRUS

Let me just give out some statistics here:

The basic unoptimized (for size) demo of the virus is about 1.5KB. This is just the academic version, written for readability without concern for size constraints.
Nops in things:

From WindowsXP SP2 and Slackware 10.1.0 note1: remember that not all NOPs are usable since some may only be 1 byte and we need a minimum of 6 bytes to insert one instruction and it's jump for the jump-chaining.
note2: freebsd uses 4-byte code alignment a lot of the time