Box
Aaron Levie, CEO
Capacity: 5 GB free; 25 GB for $9.99/month
What it's for: Collaboration
Killer feature: Users can brand Box-powered projects with their own logos and color schemes
Funding: $287 million
Number of users: 11 million
Fun fact: Levie is an amateur magician
Dropbox
Drew Houston, CEO
Capacity: 2 GB free; 100 GB for $10/month
What it's for: Backups
Killer feature: Syncs folders automatically on several devices
Funding: $257 million
Number of users: 50 million
Fun fact: will.i.am is a fan
YouSendIt
Brad Garlinghouse, CEO
Capacity: 2 GB free; 5 GB for $9.99/month
What it's for: Sending files
Killer feature: Send massive files with return receipts and download tracking
Funding: $48.7 million
Number of users: 34 million
Fun fact: Used to produce Sesame Street
SugarSync
Laura Yecies, CEO
Capacity: 5 GB free; 60 GB for $9.99/month
What it's for: Backups
Killer feature: Accessible on all operating systems and platforms
Funding: $51.5 million
Number of users: 25 million
Fun fact: Popular with the Cannes set
Google Drive
Scott Johnston, product head
Capacity: 5 GB free; 200 GB for $9.99/month
What it's for: Documents
Killer feature: Open and edit files from within a browser window
Funding: Not applicable
Number of users: 10 million
Fun fact: Larry Page is a user, natch
Microsoft SkyDrive
Chris Jones, corporate VP, Windows Live
Capacity: 7 GB free; 20 GB for $10/year
What it's for: Documents
Killer feature: Access files stored on a home PC from anywhere
Funding: Not applicable
Number of users: 60 million
Fun fact: No fun fact available
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