Box.net has dropped their app into the Android market. With 200,000 downloads over in iOS they are looking to expand their service to other devices starting with Android (good choice!!). The functionality you get with box.net is the ability to access your files/folder's from anywhere, preview docs, get to your media, share your stuff, upload files from your Android device and so on.
These cloud storage services are fantastic, if you have ever read anything about Dropbox then you will know the kind of ecosystem is being offered here...a great one! There are various different types of accounts on offer free and paid for depending on what your needs are. Why dont you check out the free account which will provide you with 1gb of storage (25meg file size maximum) to get you kicking along in the clouds. It is great to see more and more competition being introduced into Android, it will make for better products.