Plan B Forum

A guy in a bar goes to the restroom to pee. He comes back to find someone finished off his drink. Some time later the guy has to piss again but before he does he writes a note that read "I spit in this drink." He comes back and, not surprisingly, his full drink is still there. As he lifts it to his lip he looks at the note only to see someone else had scrawled "so did I."