I am building a blog page in WordPress and adding a sidebar that points to the current post. I’d like to fill that sidebar with the date of the current post using jQuery. It’s only an idea so I don’t have any code. But it would function like this:

As you scroll down the page the date (or other info) would change based on which div you were next to. It also has to work in a blog setting meaning each div can potentially be a different height.
Any thoughts?
I do not know where you want to get the date from, so, just an example.. http://jsfiddle.net/Nsubt/
Div on the right could have a fixed position or you can update its absolute position in the block working with
scrollandresizeevents.