But you'd need to use a different position if the mouse was too close to an edge, otherwise the menus would flip over eachother. And you'd need a command to do a !popup1 close, etc. (I think you have to pin them if you want more than one popup visible at a time, I could be wrong.)

scbar could do menus that head off in different directions, but it's a pathetic replacement for popup, since it lacks all the fancy features and doesn't have usable source code.