Replacements for dropbox?

Dropbox...

I’m seeing some serious replacements for Dropbox hitting the market

They all seem to have there advantages and disadvantages. Anyone used one or the other?

Ultimately I’d like to use something which is peer 2 peer, encrypted, opensource and secure. It would have clients for Android, Linux and other platforms. Webdav would be nice if you can do encryption baked in.

I like what dropbox does but I can live without the central operation. I do also like the fact dropbox is being used as a storage add on, but I’m sure this can be done using standard protocols. OAuth+Public key encryption surely can solve this problem easily enough? I’m also thinking this might also allow sharing and access control properties of folders and files within reason.