vestalesque
When someone publicly announces their interest in something incredibly obscure as a way to earn "geek cred"; dressing up for Halloween in a costume from something unknown for the sole purpose of being asked what you're dressed as.
"He dressed up as 9-Jack-9 for Halloween, but everyone thought he was doing a minstrel show. It was so vestalesque!"
"On a vestalesque impulse, she decided to start building lego versions of science-fiction ships from Space 1999."
"On a vestalesque impulse, she decided to start building lego versions of science-fiction ships from Space 1999."