File hosting services like Dropbox, SkyDrive, Google Drive, and Box all have very generous free storage levels (2 GB and up). Even so, it’s easy to quickly reach the free limit, especially as you start backing up photos, movies, and other large files. If you’re getting close to your service’s free limit, here’s a solution for quickly finding the largest of your files, so you can clean them out or back up elsewhere. This works best when you’ve set up your service to sync everything to your local Mac or Windows computer. In my case I’m using Dropbox which defaults…