File Sharing in the Cloud: BYOC (Bring Your Own Cloud)?

Virtual file shares and collaboration seem to be the rage in IT sector right now. Rightfully so, how else will we share all the documents and pictures that we create? Or centrally collaborate and track the version of the document that the whole team is working on? Sure, SharePoint has been around and is getting better, E-room is an option but can be somewhat cumbersome to manage. But users want the ability to open their files in alternate browsers not just IE, and they want to open them on different devices (tablets, phones, Macs, and Linux machines). 
Mozy has a solution, there is Box.com, and Microsoft SkyDrive, don’t forget iCloud and we have all heard of Dropbox. While all of these options are cloud based they are all public cloud hosted, which presents security questions of who owns the files and who really knows what is being shared about your content. These questions and the proliferation of corporate private clouds are what is driving VMware’s Project Octopus. I will be testing the Beta release in June, which means we are still a little far out from the Gold release, but the market is looking in that direction, and not just VMware.
How are you currently sharing files in your organization?