Geek Shirt 25: Mystralia 2006. Yes, a Myst convention specific to Australia. It happened, back in 2006. 
Also, 25 is a very important number in the Myst universe since their numbers are base-25 compared to our base-10, so I waited until the 25th shirt to wear this one.
I’m in the middle of fully stocking up one of our vending machines with cans of soft drink. I won’t be able to do it for a while because I’m going away… to Mysterium 2014, surprise surprise! Perfect shirt combo for today.
Geek shirts are on pause until I return. See you in a few weeks!