I don't know what browser you use, but my problems with getting to wrong login vanished when I installed the Firefox LJ login manager extension. You can toggle between logins with a single click, and it displays your current login nice and clearly in the bottom right-hand corner of the screen. I was forever using the wrong one before I got this, but very seldom do now - and usually only when responding to people who read both journals, when my brain obviously knows that it doesn't matter as much.