Maybe this would be better on a bumper sticker…
“My other ride’s a poo barge”
Cylons playing poker.
Not BSG-related, however it was discussed in a recent podcast:
Cookie Monster does eat cookies.
It could be white lettering on a blue t-shirt.
I just finished reading through the entire thread. Wow!!! Too many great ideas to have to choose one or two.
I’m definitely up for buying a t-shirt or two once these are made.
Ok, so I put a few more up there and I think I have a few more on the way soon. 
LOL ! Get the Frak off my Lawn !! YES ! Thanks Sean.
edit: ordered and on the way…sweet.
Oh holy frakking gods:
Larry’s Landscaping.
OMFGs.
That is the most brilliant thing EVEH!
How many different jokes does that tie together?
that. is. AWESOME!!!
Whoa, You guys used my idea!!! Cool! I am definitely going to buy one!
My picks would be and not in any particular order:
(1) Simple GWC logo t-shirt
(2) Kara Thrace and Her Special Destiny concert t-shirt with tour dates or does this one violate the whole IP thing.
(3) I waited a year for new Galactica and all I got was this stupid t-shirt
and some I didn’t see but might of been in here…
(4) GWC logo with “thanks to Chuck, Sean and Audra”
(5) GWC logo with “Tory sucks”
(6) GWC logo with “Stop pipe violence”
(7) “I am the harbinger of death” ok that might be a bit too freaky.
I am assuming direct quotes from the show fall into the category of IP, too bad 
I would of liked to see a t with a simple GWC logo on front and on the back some hybrid metaphysical vomit… lots of text quoting grandpa goo from Razor or quotes from the screamer.
Not if you add “[Bloop]” to the end.
or “Holy Frak… I’m the harbinger of death?”
Don’t you get free one?
I just ordered me some cool GWC swag. Thanks for the new shirts Sean!
“I know the way to Earth”
“Sorry, Barb.” (on back, with GWC logo on front)
“Ask me about my Pet Eight”
“Arm Porn” (especially on a sleeveless shirt)
With as ridiculous as prices are with gas, and the fact that the GWC crew are paying for their podcast out of pocket, I wouldn’t expect it. I am just happy my idea got used.
Here was what I originally had.
As you can see, Sean took it, and came up with something better.
OK, Those are cool… I think we can do something with that.
~Sean
“Talking crap about stuff…”
GWC logo
Ideally, it’d be on one of those sweatpants with the words across the butt.