I don't remember seeing this article in Air and Space Smithsonian magazine. It gives a pretty good discussion of how asteroid missions could bridge the gap between lunar and Mars missions. On page 4, however, they over-complicate the Mars mission in comparison saying that crews would be exposed to 3 years of weightlessness, when the crew would be exposed to a maximum of 7 months or so of weightlessness traveling between the planets. Of course, there's some crazy group trying to prove that the crew wouldn't need to spend any time in weightlessness.

Here is a list of old spacecraft that are still functioning. One that I work on in my day job, Landsat 5, is among 'em.