What's the weirdest place you've fought in an RP fight?
Some of the more unusual venues I've played in include a fish market, a zoo, a paintball range, the interior of a plane about to take off, and an ice cream factory. The latter probably tops my weirdness list, since the IC reason for the battle was both sides fighting over the ice cream.
There was also one particular battle where the arena itself wasn't weird (a field/forest combo), but its effects were. The fight in question was a 3v3, which would already be chaotic enough, but then the admin decided to have a bunch of aztec-style tribal warriors run into the arena and start attacking everyone indiscriminately with all kinds of weird magic. It was complete madness, with one character losing all his clothes and fighting on completely naked, another getting swallowed whole, and a third ending up covered in vomit!