XXL
Once upon a time there was SL Boutique and SL Exchange, which which everyone called sex change. Then S L Boutique was bought by the Sheep and became OnRez. Sex change turned into X Street SL because of the new Linden stricture that no one could use the Second Life name except maybe it was ok if it was followed (or preceded, presumably) by two words.

Very soon after that LL bought both sites and shuttered OnRez (the better one in my book - I kept away from XSTSL because of its ebil history). XSTSL has gone through a lot of changes of which I have no opinion as I am not involved with it, but it had no funny slang name. I always thought of it as Cross Street SL, but be that as it may, there's nothing funny or interesting about XSTSL. However, I just saw someone refer to it as "XLStreet," which made me laugh, so all is not lost.