This actually happened to me about a month ago.

I was at a party for my grandmother's birthday, and at some point happened to have a glass of orange soda, which I, being rather thirsty, finished rather quickly. I wanted to keep the glass but didn't want to hold it, so I set it down on a table, hoping no one would take it. Later:

(glass isn't there)
I . o O (Huh?  Why isn't my glass here?)
(another subself speaks up:)
I . o O (Oh, they must have GCed my glass because I forgot
         to keep a reference to it, and it had no circular
         reference (orange soda)...)