My two cents on the best protein is the stuff by Beverly. They are tough to beat on quality and taste, but I concede that they are more expensive than some of the others.
The Ultimate Muscle Protein is their newest, and it's a protein blend. The cookies and cream flavor is awesome! On a lean gain diet, I'll use it, and add some heavy cream for my fat intake. As I understand it, the heavy cream provides pure fat without any sugar, it makes the stuff taste even better, and it further slows the absorption of the protein into the body, making this ideal for a meal before bedtime.
The Ultra Size from Beverly mixes easier than the UMP, and it's also a blend. The vanilla tastes great. One nice thing about the Ultra Size is that it's extremely convenient to use if you don't want to make a shake. I'll put some in a bowl and slowly mix in some water with a spoon until it forms a pudding consistency. Add some whipping cream (or flax) and eat it with a spoon while watching TV or at work. Nice for a change of pace. You can also add sugar free flavored syrups if you get tired of the same flavors (e.g., Da Vinci syrups).
The Muscle Provider that Beverly makes is their whey product. It's very low in carbs, and so people usually switch to that when they are in the final 6-8 weeks of contest prep. I don't think it tastes quite as good, but it's not bad. I'll usually put that into a blender and add a few frozen strawberries. With the final weeks of contest prep, the awesome heavy cream is removed, and I'm stuck with flax or fish oil. Contest prep sucks on so many levels! MP is also popular as a post-workout shake with a bunch of fast acting carbs (e.g., their Mass Maker product).
$$$ is always an issue, but since protein is the base substrate (w/o gear, at least), if you're gonna blow money on one of your supplements, doing it with your protein source may not be a bad idea. Having said that, if you can't afford it, buy an affordable protein blend and make sure you're getting about 1-2 grams per pound of lean mass per day. I shoot for 1.5 g/lb/day.