13 Add an extra layer of protection to Dropbox's own security by creating an encrypted container within your Dropbox folder. Several third-party utilities--including TrueCrypt--will help you do so; or you can use OS X's own Disk Utility to create an encrypted disk image. Don't use OS X's FileVault with Dropbox; they do not get along.
14 Programmers: Check an Xcode project out of the source-control system at work and into a Dropbox folder. At home that night, fire up Xcode, pointing it at the same Dropbox folder, and continue working. When you get back to work the next day, check the project back into source control.
15 Web developers: Use Dropbox to store "local" copies of files you're working with on live servers. As you change those files, from different locations, they'll synchronize, so you'll always have current copies to work on.
16 Move the Web Receipts folder to Dropbox, and then edit the Save To Web Receipts Folder workflow so it points to the new location. Unfortunately, because that workflow is actually a Python script, editing it is nontrivial; you can't use Automator to do it. The instructions are available online, if you care to search. It's probably simpler to just create a new Save Receipts shortcut instead.
To do so, navigate to /Library/PDF Services and move the existing Save PDF to Web Receipts Folder.pdfworkflow script somewhere else for safekeeping. Now move the Web Receipts folder from your Documents folder to Dropbox. Make an alias of it (not a symbolic link), and drag that alias into /Library/PDF Services. If you want to, you can rename the alias to make it more active--'Save To Receipts Folder,' perhaps.
17 Keep your iWeb domain files in Dropbox. (By default, they're in ~/Library/Application Support/iWeb/Domain.)
18 Store all your plain-text notes in Dropbox. Plain text is the ideal cross-platform format, and there are many, many text editors (for both OS X and iOS) that are Dropbox-friendly.
19 Synchronize your browser bookmarks. If you use Safari, that means moving the folder ~/Library/Safari to Dropbox, and then creating a symbolic link from the old location to the new.
Firefox stores its bookmarks in a file called 'places .sqlite,' which is buried in the folder ~/Library/Application Support/Firefox/Profiles/randomsequenceofcharacters.default. You could synchronize that one file in Dropbox as you do other files. Or you could synchronize your entire profile‚ which includes your history, saved tabs, and more, in addition to bookmarks, by synchronizing that entire folder.
20 If you'd rather not go to the trouble of synchronizing bookmark files or profiles, you can always sync .webloc files linking to specific Websites.