Technology blog Tested goes in depth to explain Windows symlinks (symbolic links that let you do all sorts of cool things like sync files and folders outside your Dropbox folder), detailing what they are and how to use them.
We've talked about how to use symlinks in OS X and Linux in the past, and shown you how to use them for specific things in Windows, but we've never gone in depth on Windows symlinks. Tested's guide nicely explains how to create symlinks in Windows and offers suggestions for when you might benefit from a symlink. For example:
mklink /j "c:usersWillMusiciTunesiTunes Music" d:Music - This line makes a symlink that redirects from the folder c:usersWillMusiciTunesiTunes Music to the Music folder on my second hard drive. This type of use is especially handy if you have a small main hard drive and a larger secondary drive.
Granted, in many instances you'll be better off just changing whatever settings you can so that an application is pointing at the right directory and you don't need a symlink, but knowing how to set up and use a good symlink can be really handy in the right circumstances.