Modern art: wheeeee!
The TM used to be a power plant, which explains why the main hall is 115 feet high and 500 feet long (and is known as Turbine Hall). That's a tough space to fill; there are few pieces of art that could live comfortably in such an area without being overwhelmed by the building itself.
So what better than a whole bunch of slides?
Carsten Höller's installation, Test Site, is exactly the kind of art you could never hope to find in the US, as it involves encouraging people to send themselves hurtling through enclosed steel-and-plastic tubes.
We elected not to try the tallest version, which started up on the fifth floor (partly because you needed tickets, but mostly because of the almost-vertical drop after the first turn), and instead opted for the shortest slide (which was a relatively safe twenty-foot drop).
Check out video of the slides--it's just like being there! Except safer!