I only did this on the Bug, but I left a socket wrench hanging onto the alternator pulley bolt and forgot. Then I started the car.
Took me an hour to find the wrench in my neighbor's back yard...
2009 ML350 (84K) - Family vehicle
2001 CLK430 Cabriolet (71K) - Wife's car
2005 BMW 645CI (124K) - My daily driver
2012 Mustang V6 (60K) - Daughter's car