Make it a little bit more healthy by adding some flaxmeal, some greens or even oats. Bananas are a perfect sweetener. And if you freeze them for two hours it tastes like a real ice cream shake. Peel and slice the bananas before putting them into the freezer. Dates or other dried fruit work as sweetener either. Or try frozen fruit mixes (the unsweetened ones) from the supermarket.
Right now I drink two bananas mixed with some soymilk, about two heaping spoons of flaxmeal, one spoon of unsweetened cocoa and a few drops of vanilla extract. It's soo yummy and fills me up for a few hours I bet.
P.S. Yes, I reuse my straw..