Try this one Andy.
We have one of those here, tallest in the Southern Hemisphere. 328metres, with clear glass floors on one of the viewing platforms. Even if you don't get vertigo, throws the eye for a moment.
http://www.skycityauckland.co.nz/Attrac ... tower.html
You can walk around it: http://www.skywalk.co.nz
You can jump off it: http://www.skyjump.co.nz/
It's bad enough being up there, let alone standing on glass but why the hell would you want to jump off it as well!!