I really like the MSN notification popup. Basically the popup you see when you receive a new email etc. I'd like to put timers and set times so I, for instance, get a popup at 2PM saying "Don't forget..." I know I could make my own notification bubble but I'd prefer the WLM one.
Thanks
The answers in this question might help you: http://stackoverflow.com/questions/506806/is-it-possible-to-programmatically-talk-to-msn-messenger-live-messenger. Looks like there might be libraries that might allow you to make the api calls you want.
Failing finding a way to talk to WLM directly, you may want to consider making your own notification bubble and make it look identical to the one in WLM.
Take a look in the site Live Services. You'll find some cool information about API's that can be used, but to do what you want you should look at "Alerts". This is the right way to do that.
MSNP-Sharp is a very good C# API that will allow you to connect to WLM and send messages.