I got used to using confluence-mode to be able to open wiki pages hosted on a confluence server using my emacs client locally:
http://www.emacswiki.org/emacs/ConfluenceMode
Is there anything equivalent to be able to create/edit wiki pages from a github.com repository in a similar fashion?
The basics of what I usually do are:
Setting up my URL:
'(confluence-url "https://myconfluence.server.somewhere/rpc/xmlrpc")
Create/Edit pages from emacs:
M-x confluence-get-page
From then on, it's like any kind of buffer, but it creates/opens/saves files via xmlrpc.
Anything like that but for github.com wikis?
Considering a GitHub wiki is simply a git repo, you can clone it locally, modify it, make new commits and push back.
See "How do I clone a github wiki?".
With a package like magit, you can do all that from your Emacs (see magit documentation).
For instance, once the commits are done:
Typing P P will only push the current branch to the remote. In other words, it will run
git push <remote> <branch>
.