Sort by Comments?

Is there a way to sort by posts that have been most recently commented on?

Here’s my problem: I’m creating posts and then a lot of people include their input by commenting on them. But whenever I or they return to the site, we have to root through all of the posts and remember the number of comments for each post. Know what I mean?

Say I have 6 posts I’m keeping an eye on, so when I return to the site I not only need to scroll and find those particular posts, but I need to remember what the number of comments was for each post to tell if there’s anything new. I’d like it to just throw the most recently commented posts at the top of the page. It’d be best if it didn’t do it on the front page, but instead when sorted by category… Is this possible?

I’m running 1.5. (Which is GREAT, BTW.)

Thanks in advance.