A while ago I wrote about Grabbox, a nifty Mac OS X utility that allows users to share screenshots via Dropbox. Today I stumbled across an equivalent app for Windows: Dropbox Screen Grabber. It allows you to take screenshots using a predefined hotkey combination and then instantly uploads them to your Dropbox public folder, while the URL of the uploaded file can placed on your clipboard to make sharing the screenshots really easy.
You can elect to take screenshots of the whole screen or just the active window. Dropbox Screen Grabber actually has a few features that make it a little more versatile than Grabbox: You can redefine the hotkey combination; automatically resize screenshots before uploading them; and control which Dropbox folder they are uploaded to. You can also use it to automatically upload screenshots of your desktop at predetermined intervals, which could be useful if you want to monitor or record a process, for example.
Dropbox Screen Grabber is a free download from the Dropbox Addons wiki. Users of multi-monitor setups beware: it has a known bug that means it will only take screenshots on the primary monitor.