I always wondered why no one did this to heat milk safely...can i just pour some milk where the water would normally go and just wait for it to come out?

I would use the microwave instead.

Hmmm..actually that's not a bad idea. I bet it would work fine. Just remember the milk will be scalding and hotter than you probably want it.

It would most likely burn and leave a residue on the heating elements inside the water tank. Try it if you want but it would take a lot of effort to clean and it would be much faster to use a microwave.

My coffee maker has a milk frother which heats the milk up anyway.

I really don't think that would be a great idea. In general, water for coffee is heated to around 190 degrees F and I think this would "burn" the milk and leave a residue in your coffee maker, which would then affect all of your coffee thereafter. I like the microwave idea or using a sauce pan myself to control the heating. But, you can always try and let us know...