Is there a way I can password protect a dropbox directory on my work pc?

Password-protecting the folder won't really do a whole lot if they can just log in as an administrator and claim ownership of the directory themselves.

I'd suggest installing TrueCrypt, and using that to create a file-based encrypted volume. Then put your DropBox directory inside that, and only folks who know the decryption password can get to it.

Note that they could easily install a keylogger on your PC to learn your decryption password without your knowledge.

Also, the requisite disclaimer: Check with your IT department, and don't do anything contrary to established IT policy. Oftentimes organizations frown on personal use of work property (your PC) and resources (the bandwidth used to download from/upload to DropBox), so make sure you aren't violating any rules that could land you in trouble.

I would reccomend using this website:

http://www.howtogeek.com/105633/how-to-create-a-password-protected-folder-without-any-extra-software/

It does not actually encrypt your files or protect them in any way at all, it just hides them. It seems to me like you don't really need any high level security here, you just don't want people going through your personal files, so this would work great. I use this on a public computer I use at school, and it works like a charm. With the folder hidden, even if someone clicks on the dropbox app, it won't open. Other people can access your data, but it will take more work that the average guy will be willing to put into it.

I realize this is a late addition to this post, but I figure that anyone searching for an answer will now be able to use this if they want.