[Vanquish]

Is it possible in OSX to password protect folder ? If so, what app/CLI-command do I need to use ?

[CharlesS]

Just deny read access to the users you don't want accessing it, using standard UNIX permissions.

You can modify the permissions of a folder with Get Info - you don't even need the command line.

[Vanquish]

yeah, I know I can do that but I want a double security. In case someone has physical access to my logged in account.

[stew]

Use encrypted disk images.

[AsahiToro]

Try the app called LameSecure. You can find it on versiontracker. Only problem is that it still shows and opens the locked folder if the folder is in the recent folders menu item in the Finder's Go menu. Once that folder get's buried after opening other folders, that kind of takes care of itself though. Other than that it works pretty well.