You could take this post as a second iteration on this older post.
There are many urls that are fairly navigable on w3m (emacs-w3m that is). The less html-y the site is, the more confortable it is.
So here's a way to redirect gist links to the raw plaintext counterparts. I just wrote it in 5 minutes, and it's quite inestable, but for the moment, it Works On My Machine. I'll try to make it more general and robust in next few days (as always, with advice from davazp)
Btw, it doesn't work if there is more than 1 file in the gist.