I call this one my happy shirt
This one always cracks me up (“Pepe! Talk to me!”).
This one always cracks my coworkers up, specially those who like me are part of the early morning contingent and have thus been told many times “joder tío eres la leche ¡que no son horas!” (“dude, you’re the milk/you’re too much/cut this out, it’s way too early!”). Having the text be in English when the joke is actually one that does not work in English gets extra points, as we tend to have a lot of problems with translations.
I have one that’s black with a big red Mario Bros mushroom which says “grow up”; its green sister, with a green mushroom, “get a life”.
For the cricket tragics, the official record of a day of infamy.
Trent Bridge 6th August 2015
Bumped.
Some funny ones I’ve seen recently:
I could agree with you, but then we’d both be wrong.
Irony - the opposite of wrinkly.
Let me save you some time: I have lousy references.
I can explain it to you, but I can’t understand it for you.
History Buff: I’d find you more interesting if you were dead.
To save time, let’s assume I know everything.
Bigfoot saw me, but no one believes him.
In my defense, I was left unsupervised.
My password is the last eight digits of pi.
It’s not hoarding if it’s books.
With enough thrust, pigs fly just fine.
I sometimes wonder what happened to the people who asked me for directions.
A T-shirt I recently created. 
I saw this one in Vienna – it’s got some meta-humor going on, since Austrians frequently get mixed up with Those Other People. Motmot Yo-Yo and T-Shirts on Instagram: "Split fountain! Yes we can do this! #motmot #screenprinting #splitfountain #design #kangaroo #austria #tshirt"
Awww…now I miss [del]Olives[/del] I mean Spice Weasel.
Yeah; I thought the same thing when I opened this thread just now.
I hope she is well and happy.
I got this for Christmas last year
Did you see the Rick and Morty episode with a big Zardoz-style flying head?
I want thishistory shirt.
I have a friend who’s a spectacular fantasy artist, and I just bought this shirt from his store. It makes me giggle, but I’m an enormous nerd.
Here’s one for Python fans. I actually happened upon a group of college kids cosplaying a scene from “Holy Grail” while I was wearing this shirt. They were quite excited over it.
My favorite.
I would love to have a T-shirt with the Adam West Batman, coupled with Sir Robin from Holy Grail, with the caption:
“HOLY HAND GRENADE, BATMAN!”
If anyone is a t-shirt designer and creates that, you may have that design for 2 shirts per year, on demand. 
There was a flying Zardoz head on an early episode of Rick and Morty: http://i.kinja-img.com/gawker-media/image/upload/s--FRuPGVOo--/gkiqmxdt6vmjvgaoe4c6.gif
Some other good T-shirts I’ve seen recently:
In my day we had NINE planets.
And yet despite the look on my face, you’re still talking.
I can’t believe how old people my age are.
You know that little thing inside your head that keeps you from saying things you shouldn’t? Yeah, I don’t have one of those.
FAA Mission Statement: We’re not happy until you’re not happy.
Surely not EVERYONE was Kung Fu fighting?
I had one with the Chicago flag on the front of it that said “Welcome to Chicago” and on the back it said “Now go the fuck home”
It’s getting a little historic now but this onewhich I got this for my son tells the whole embarrassing story with excruciating accuracy and yet fits in a tweet.
Explain, please?