My wife found this recipe a while back, and let me tell you it has been a family favorite ever since.
You'll need the following ingredients
First, toast the bagels a little. Smear each half of a bagel with BBQ sauce, top with ham, then pineapple, then the cheese (My wife tells me that I, for the umpteenth time today, have made a critical error and that the pineapple goes between the ham and BBQ sauce).
Broil, open faced, until cheese is all melted. If you broil on Med or Low, you'll probably heat it up a little better. High tends to melt and burn the cheese while everything else is more like room temperature.
I totally love these things and even make them at work from time to time.