IsoPure drinks are pretty burly. Try one first before filling the cupboard with it, like I did. Fortunately, GNC happily refunded my money...they're good to deal with.
Plain whey powder has an unfortunate cheesy flavor that is very pronounced in a lot of fruit-based drinks. It blends in well with chocolate or vanilla flavors, however. Plus there's the lactose-intolerance to consider.
I've been relying heavily on lassi, an Indian yogurt-based drink. Very refreshing in the summer, and high-Protein. It can be made with simply spices and a little sweetener, or with fruit...a "salty" lassi can also be made using cucumbers or bell peppers (strain before drinking). There's recipes out on the web for all of it.
There's soy Proteins that come in many forms...tofu, tempeh, miso, and powders. More neutral in flavor than whey. Not sure why soy has the stigma it seems to suffer from...I've always liked it, and it's easy to work with. Miso broth tastes good, and has lots of protein.