--when someone discovers the old Pokemon roleplay forum on Proboards that you belonged to back in 2004, and you immediately remember the characters you played, the regulars you hung out with, your login, and what you were doing in real life at the time.
But on the same day you get an email from Livejournal about an account you created only last year for a Professor Layton roleplay, and your response is "what the fuck is this?" because you'd completely forgotten it existed and even your own posts are unfamiliar to you when you read them.
I somehow had a longer attention span when I was fifteen, apparently.
That, and the Layton characters I play are the ones nobody cares about. XD