At least on OS X, different users can be logged in to different Dropbox accounts at the same time. So you could use different user accounts for your different

At least on OS X, different users can be logged in to different Dropbox accounts at the same time. So you could use different user accounts for your different tasks, or work out something with shared directories. But, yeah, it's not user friendly, and it's hard to imagine Dropbox adding support to the regular client.