[kerowo]

[ QUOTE ]
Next time, steal the offending dish, place in ziploc and hide. Repeat a few times. When annoying slob outs him/herself, wait until after work and place the grungy dishes (now sans ziploc protection) in his/her cubicle. They'll enjoy a great morning the next day and will probably be less likely to re-offend.

[/ QUOTE ]

Or just put up a note saying you are going to be throwing away any dish left in the sink when you show up in the morning. Then do that.