"Make it so."
These are the pros: 1) they go with pretty much any thing (even a lab coat), 2) when you look down (which is fairly often as your grant writing beats you down) you'll see a vision of sunshine and hope, 3) they are relatively affordable, and (the best part) 4) all the cool kids are doing it. So you can tell everyone that despite the fact that you are holed up in whatever personal box of graduate student misery, you are at least up with the latest fashion. So there, get some Soludos. Go and at least let your feet have some summer fun. This post is endorsed by my research assistant. (fig. 2)