I have... at least thirteen Dreamwidth journals at the moment, most of them for the purpose of RP. The one thing that I would really need implemented in a multiple account feature like this would be the ability to choose a different account's various userpics when I comment. It does me no good to "post as this account" while still logged in to my main if I can't choose icons on my secondary... which is mostly the point of logging into those secondaries to post anyway. Otherwise I'd just use the "post as a different account" feature. :)