What are some alternatives?
Google Drive - Google Drive is a personal cloud storage service from Google that lets users store and synchronize digital content across computers, laptops and mobile devices, including Android-powered tablet and smartphone devices.
Mega - Secure File Storage and collaboration
ownCloud - ownCloud is an open source project enabling businesses to host their own cloud storage while maintaining regulatory and compliance needs.
SpiderOak - SpiderOak makes it possible for you to privately store, sync, share & access your data from everywhere.
Microsoft OneDrive - Secure access, sharing & file storage
SugarSync - SugarSync is a cloud file sharing, file sync and online backup service that is simple, powerful and easy to use. Get a 30 day free trial!