YouSendIt is a service that makes it easy to share large files with anyone. The free account includes 2GB of storage, 5 e-signatures, and a 50MB file size limit. You can add more features and memory for a fee.
YouSendIt allows you to easily send and receive files through you email without worrying about your inbox limits. You can also share folders and sync your files and folders for offline access on your devices. You can also sign online documnets from your computer, smartphone or tablet.
This last feature is a pretty cool one for anyone who hates downloading a file to sign it, than rescan it to resend it.
There is an Android app and an iOS app (although that is still Beta) so you can use it on the go.
Dropbox - file sync, share, store - my favorite
Justbeamit - transfer large files easily - http://educationaltechnologyguy.blogspot.com/2011/10/justbeamit-transfer-large-files-easily.html
Gett - http://educationaltechnologyguy.blogspot.com/2010/12/gett-gett-free-service-to-share-files.html
FileStork - http://educationaltechnologyguy.blogspot.com/2011/07/filestork-request-files-from-anyone.html
Fyles - http://educationaltechnologyguy.blogspot.com/2011/05/fyels-free-easy-simple-file-sharing.html
AVG LiveKive - http://educationaltechnologyguy.blogspot.com/2011/04/avg-launches-file-sync-backup-and-share.html
AirDropper - http://educationaltechnologyguy.blogspot.com/2010/12/airdropper-request-file-from-anyone.html