Is there a name for that thing that happens where people redundantly tack the last word from an acronym onto the acronym, as in "PIN number" and "ATM machine"? Yesterday John did it with "BFF's forever," which I'm sure is the name of several Facebook groups. I was talking to a guy at a party once several years ago about this phenomenon, and the example he gave was "stupid hat party party." Whether or not there is such a thing as a stupid hat party (party), this is still my favorite example.
Update: It's known as RAS syndrome (redundant acronym syndrome syndrome).