You should be glad AiN; you know they're going to be better than the first or second generation designs.
Hydro is a good option if the dams already exist; building new dams is incredibly costly and terrible for the environment.
I read a while back about some guy who wanted to build fields full of
Stirling Engines in the desert. The advantage here is that each one is fairly cheap, easy to maintain and needs nothing more than heat to operate; it doesn't even need direct sunlight like solar panels do. The guy was looking for money from small investors; mom-and-pop put in a few grand, buy one engine in the field and get a slow but steady income from the electricity generated. I have no idea whether it will end up being cost effective, but I love it as an idea anyway.