I'd like to suggest modifying the function of $tip to allow placement at any corner (maybe even sliding in from side or top), and to be usable even if mIRC is the active app.
I have managed to use custom windows to achieve the same effect, but that kind of "notification" steals the focus. $tip works perfect for me in this regard aside from the desired functions I mentioned above.
I would use this as an alternate to the NOTIFY messages that appear when someone logs on in your notify list. I prefer to keep those messages out of my channel and chat logs, but I also would like to know instantly when someone logs on. I think this would be a good alternative.