Meh... I found an extra key on my key ring... and I have no idea where it came from.
Can't imagine I added a key and forgot about it... but I don't want to throw it away incase it goes to something important... which... if it's on my personal keychain... it should.
I highly suspect someone is messing with me... and they know me well enough to know it will bug the hell out of me not knowing where it came from or what it goes to.