#3 Google Drive

Google Drive is a file storage and synchronization service by Google. It is now the home of Google Docs, a suite of productivity applications that offer collaborative editing on documents, spreadsheets, presentations, and more.

Google Drive gives all users 5 GB of cloud storage to start with. A user can get additional storage, which is shared between Picasa and Google Drive, from 25 GB up to 16 TB through a paid monthly subscription plan ($2.49 US per month for 25 GB).

Gmail is well integrated with Google Drive. Just sign in to your email account and click 'Drive' on the top bar. Select the files you want to share (multiples possible), add email addresses and click send.

#2 Outlook- SkyDrive

SkyDrive, also known as Microsoft SkyDrive, previously Windows Live SkyDrive and Windows Live Folders, is a file hosting service that allows users to upload and sync files to a cloud storage and then access them from a Web browser or their local device. It is part of the Windows Live range of online services and allows users to keep the files private, share them with contacts, or make the files public. Publicly shared files do not require a Microsoft account to access.

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