I'm a fan of Unique powder, originally a Hercules brand, but more recently manufactured by Alliant. It's a darned versatile powder, good for many, many uses. If you own a caliber, there is probably a load for it that uses Unique. It's not the best powder for every application, but it's a good powder for a lot of applications. If I had to pare down all the reloading powders on my bench to just two or three, Unique would be sitting on the shelf.
This guy seems to like it too. Go there and read.
Thanks, Joe, for the link.