more cloud providers

Git-annex already supports storing large files in several cloud providers via special remotes. More should be added, such as:

Google drive (attractive because it's free, only 5 gb tho)
Owncloud (has several providers; at least one provides 5 gb free; open DAV based API)
OpenStack Swift (teh future)
Box.com (it's free, and current method is hard to set up and a sorta shakey; a better method would be to use its API) done
Dropbox? That would be ironic.. Via its API, presumably.
?Amazon Glacier done
Internet Archive done
Mediafire provides 50gb free and has a REST API.
Flickr provides 1 tb (!!!!) to free accounts, and can store at least photos and videos. https://github.com/ricardobeat/filr is a hack to allow storing any type of file on Flickr.
mega.co.nz. Already supported via megaannex, would just need webapp modifications to configure it. May want to use megaannex as-is to build a non-hook special remote in haskell.