Resorting Posts with Links?

Hello-

What’s the best way to give the user the option to resort the posts by clicking a link?

For example, I have a posts with tag X, and some other posts with tag Y. By default, all posts with tag X and tag y are shown. Is there a way to have it so there is a link at the top that when clicked, resorts the post to only show posts with tag X?

Thanks!