Even more impressive than this hello world and with 29 byte just 3 byte bigger:

  b013cd10c52f0f3197b18cb38cfe018009804b75f881c74001e2f0ebe9

I made this in 2001 and used it once in a job interview, I asked for access to a computer running XP, opened cmd.exe and debug.exe, entered the asm code (rdtsc is not supported by debug.exe but i remembered the 0f31 opcode) and blew someones mind.