While on the subject...
There's a reality show called Money Morons in which an expert helps couples get their finances on track. In every episode, the expert meets with the couple and reviews their monthly expenditures (mortgage, groceries, entertainment, transportation, etc.) which have been tracked right down to the dollar. I've seen a few episodes where the expert confronts the husband with "You took $450 in cash from the bank that's unaccounted for. What did you spend it on?!" to which he, flummoxed and guilty, replies "Uh...I have no idea where that went...". Whenever I see this I think "I have a pretty good idea where it went...".