Someday, I'd like to see a nice library written in something like O'Caml or Haskell exposed as a C interface that exists solely to be a library. I know it's technically possible today, but it doesn't seem to have penetrated into the public consciousness that even a C library doesn't actually have to be written in C anymore. (It may not be slick yet, but only because people aren't doing it, chicken and egg. There's no fundamental stopper.) I sure as hell wouldn't write a "C" library in C if I had anything remotely resembling a choice.

(Of course, that only solves string bobbles, not the "infinite memory consumption required" problem, but even then those other languages can have somewhat cleaner, clever solutions than in C.)