|Grow a pair and try your carrot soup cold.|
Stock--Add a little soy sauce to pretty much any stock, and then start writing a letter to thank me. It'll change your soup world. Soy packs lots of umami, which is that elusive fifth flavor your tongue can pick up on.
Parmesan rinds--Toss 'em into your soups and simmer. It'll change the flavor of your soup, and give you some delish cheesy goodness. Be careful of this in a bean soup--it can bind right up with the fiber and leave you with a gooey mess.
Tofu--A great thickening agent. Just blend it up and use in place of cream.
Cannellini beans--Another thickening agent from the dieting gods. Blend and mix 'em right in. Delish.