What is URL Droplet?

Lifehacker summed it up quite nicely. URL Droplet is a simple webapp that allows you to paste in the download link for a file and have it download straight to your Dropbox, so you can deal with later. You could start a large download while out on your mobile phone, on a company computer at work, or just sitting at an internet cafe.

For the moment it is free to use, but servers do cost money so some upcoming features will only be available at a premium.