Do you own a USB key? Have you ever emailed a file to yourself? Ever deal with the frustration of going to access a file and then realizing it’s on another computer? Those days can now be left behind. I bring to you Dropbox.

Dropbox is a tool I have used for quite some time since it was in its early beta stages, and have found it very useful and thought perhaps I should share it with you. Dropbox is a software that syncs your files online and across your computers. You just install Dropbox on all of your computers, and practically like magic you can access any files you save to Dropbox through any of those computers. It keeps all of your files in sync, when you save a file on one computer it’s as if you saved it on all of them. This gives you the ability to work on any of your computers and have access to all of the files you need.

This syncing also in turns creates a perfect back up utility. The 2 gigabytes of storage that comes with a free account is more than enough for most people to store their important documents, but more space is available with paid plans. Every time you save a file in your Dropbox it’s saved on their server, so it something drastic happens on one of your computers you can easily access files in your Dropbox from another computer or from that same computer once you have got it working once again.

In addition to keeping your files in sync across multiple machines, Dropbox also keeps a history of your files for you. Dropbox can help you undo changes you saved to a file or even undelete a file you deleted by mistake. On more than one occasion I’ve accidentally saved changes to a document that I didn’t mean to save and then exited the program I was using. At that time the programs undo history becomes useless, but with Dropbox I have been saved. By default, they keep 30 days of history on your files, but you can enable it to unlimited with their “Pack-rat” option.

Not only can you use Dropbox to keep your files in sync across multiple computers, but you can also use it to share your files with other people. You can easily share files or entire folders with Dropbox. There’s even a nice feature that allows you to share your photos (or other images) as a photo gallery. Simply put the folders you want to share in your Dropbox and invite people to those folders. You can even create a public url for your files to share specific files within your Dropbox. I use this feature in Dropbox for projects at work to easily share files and documentation with other people I work with.

Overall, I love Dropbox and I thought you might too, so I felt it’d be best to share. I use it both for business and personal uses. It replaces having to worry about email attachments, USB keys, and backup software. It’s all there in one nice and, in most cases, free package.