There's another one that just came to mind, it involves drinking as well. Doh
I was asleep after a night on the town with my girlfriend, when i woke up because i had to pee. I went downstairs to the bathroom, and did what i came for. At least that's what i thought. Apparently i was dreaming and sleepwalking both at the same time. While in my dream i went downstairs to the bathroom, in reality i walked around the bed, to the side where my girlfriend was sleeping, and peed all over her. When i was done i walked back to my side of the bed, got back in, and fell asleep again. I didn't notice a single thing of whatever my girlfriend's reaction was. He told me the next day she cursed me out, took a shower, and went to bed in one of the guestrooms.
I still can't believe i did that, it's all a big blur to me.