Here is a great and interesting animation/talk about Quantum Mechanics of macroscopic objects, in particular a recent experiment using "Heisenberg's Microscope".

[www.youtube.com]

Note they didnt actually get to zero Kelvin for the experiment, but got the temperature to less than 100 milliKelvin (I think the actual temperature was 25 mK) see press release here [www.caltech.edu] and the paper is available here [arxiv.org]

Jonny