For the college-aged (and graduate-student-aged) among you, I wanted to point out that the NASA Robotics Academy is accepting applications for its 2008 summer program. Students are hired to work on projects in teams of 4-5 at either Goddard or Marshall Space Flight Center. The internship is residential (you'll live with other interns) and it does include a stipend.
I'm an alum of the 2005 program (its inaugural year) when I worked on a planetary rover design project with Goddard in conjunction with a lab at the University of Maryland; it was a good time and the trips to see other robotics labs -- we went to Johnson Space Center, MIT's CSAIL, and Carnegie Mellon's Robotics Institute -- was unbeatable.
Also, you get a discount at the NASA gift shops. Just saying.
Application deadline is 15 January, and you'll need some recommendations, so get crackin'!