You may be interested in Merge Algorithm (Combining Sorted Lists)
. In it, I provided a more generic (higher order) approach to fetching items from the lists.
You may also be interested in an article I wrote for perl.com on Understanding And Using Iterators.
Do you use iterators a lot at work? I once combined 4 different iterators to solve a problem and was wondering if anyone had ever used more. I am rather passionate about iterators because my brain seems to have a hard time thinking recursively.