(It is rather hacky, because I haven't yet bothered fixing a nice URL for it, so you'll have to change the URL in the future, but it should work)
(import "http://github.com/pereckerdal/termite/raw/b60c4ee3943b1502cfd5e5f47530b17467... ")
Btw, you could (and ought to) use this URL instead:
http://github.com/pereckerdal/termite/raw/master/termite.scm
Otherwise you'd be locked to using a certain version.
Barring the rather long URL, this is by the way rather awesome; It means that you can develop a BH library or application, push it to GitHub and then voila you have a URL that others can use to import the library. This also works for libraries with dependencies to other libraries. With some toying around with symlinks in BH's work directory you can override so that BH will use your local copy of the library even when using the package URL.
I'm curious to see how this idea scales.
/Per