For hosting common files it's ok. Also it is on Android too do, great to transfer files between your Windows and your phone. But if you want better security you have to subscribe a monthly offer.
Dropbox - Online Sync and File Sharing
Box - Box offers secure content management and collaboration for individuals, teams and businesses, enabling secure file sharing and access to your files online.
Google Drive - Access and sync your files anywhere
Mega - Secure File Storage and collaboration
SpiderOak - SpiderOak makes it possible for you to privately store, sync, share & access your data from everywhere.
CloudApp - CloudApp allows you to share images, links, music, videos and files. Here is how it works: choose a file, drag it to the menubar and let us take care of the rest.