So my first experience with physics research was with the Gravity Probe B project, where I worked part-time for my first few years in college. GPB is a satellite mission, 40 years in the making, designed to measure frame-dragging -- a fairly subtle prediction of Einstein's General Theory of Relativity. GPB also amounted to a full-employment program for physics undergrads - at any rate, they allowed me to play around with physics experiments without a lot of pressure to churn out hard results. It was pretty cool introduction to physics research, but ultimately not the sort of project I was really interested in, so I eventually moved on to other stuff.
After going to grad school I realized that many astrophysicists actually held a rather dim view of GPB for a lot of different reasons. Dan Holz has an excellent post that explains the science behind the project, and some of the discontent.
Anyway, after 40 years of planning they finally launched the sucker in 2004 and were planning to unveil their Big Result this past weekend when suddenly ... they decided they needed more time to finish the exam. I guess what's a few more months of waiting after 40 years.