That's a Czech phrase about being really thirsty. It means, literally, "I have a thirst like a girder." I guess you need a big drink to satisfy a thirst like that, but I never realized that girders and joists and crossbeams (oh my!) got thirsty.
I'd rather be thirsty like a monkey—at least they can scamper to the nearest water source. It's hard to do that if you're a girder.
If you are a monkey and live in Brno, then you can scamper on down to the "At the Thirsty Monkey" wine bar, just over the hill from NvB headquarters.
Tags: brno, czech, signs