I couldn't believe this when I saw it: a 75mm recoilless rifle mounted to an Italian Vespa scooter.
It's for real, too. Roughly 800 AMCA Troupes Aeról Portées Mle. 5s were used by French Airborne Forces in Algeria and Indochina (Viet Nam).
-from Wikipedia
ps. That sure looks like a sub sandwich up front, doesn't it?