Ask YC: Workplace experiments?

37 Signals, those blogging wunderkind, have been posting about <a href="http://www.37signals.com/svn/posts/893-workplace-experiments">various workplace experiments</a>.

I especially like the unconventional hours bit, but it got me thinking-- what other workplace experiments are worth doing?

Office vs. open is pretty tough, since that requires changing your actual workspace, but many other things would be testable.

What ideas do you have on this?