multiple content fields for each page/post

I am looking for a plugin that would provide a way of defining multiple content for each page or post. This is similar to the question of every page having its own distinct sidebar, but I was hoping for something perhaps simpler (or maybe more complicated!)

Basically, I want to have a main content field for each page/post, and a separate links area that would float in a box in the top-right corner of the page/post.

Any ideas?