Dropbox is a great software for synchronizing your files across all the computers you use. You can register a 2 GB account for free, and by referring people, you can increase your account up to 10 GB. It makes a folder on your computer, and whatever files you put in there will be automatically uploaded to your Dropbox account and downloaded to all the computers that you use. You can also log into your account from any computer and download your files from it. You can also share a folder with your friends, and whatever any of them puts into that folder will be automatically be downloaded to all your computers. Also you can make a public link for the files you want to share, from which anyone can download them, just by putting them in your public folder. It also has an iPhone app (and a soon to be released Android app) with which you can sync your files to your iPhone and Android!!!
Other nice features:
* Lan syncing: If one of the computers that is linked to your account or the account of someone with whom you have shared a folder is on the same LAN as your computer, then the files between them will be synced across the LAN!
* Single-instance storage: If you put a file in your Dropbox folder which has already been uploaded to their servers by someone else, then Dropbox will recognize that and won't upload the file again. The file will just get assigned to your account!
* Delta sync: If you make some changes to a big file then only the change will be uploaded, not the whole file; this can save a lot of bandwidth and annoyance.
* File versioning and restore: When you make changes to a file in your account, Dropbox retains the previous version of the file in your account for thirty days (which can be downloaded again if needed). Similarly if you delete a file then the deleted file remains in your account for a month, during which time it can be restored. The great thing is that these files don't take up any space in your account! Also if you have a paid account, you can buy the Pack-Rat feature, with which the previous versions and deleted files can be restored from your account forever!!!
* Multi-platform: It works on all the major platforms, Windows, Linux, and Mac OSX.
* Security and compression: The files are sent on a secure connection to the servers, and are encrypted with very good encryption techniques there. Also the files are sent in compressed state to minimize upload and download time.
So sign up for this great service!! Sign up on this link and you will get 250 MB extra in your account: https://www.dropbox.com/referrals/NTE1MjU2MjE5
Then download and install the Dropbox app from their site and you're set!