NASA is looking for a name for the next Mars rover, officially called the Mars Science Laboratory. They've decided to have a contest, and it's open to school children up to 18 years of age.
The rovers so far (Sojourner, Spirit, Opportunity) have all had serious names, so I doubt they'll go for Marvin, which would really just be perfect. How about Wells? I suppose John Carter is out. Ray Walston?
Of course, given how over-budget MSL is, and how it's threatened other missions, they might want to name it Gilligan. Somehow, I doubt they'd go for that, either!
Anyway, if you're a teacher or a school kid, check that site out and give it some thought. Your idea may wind up traveling millions of kilometers to another planet, and that's pretty cool.