I have been exhorted repeatedly to write more content. But if I did, would I be content? Love those puns. :)
Anyway, the Kryogenix House of Javascript Weirdness presents sortable tables, an unobtrusive DHTML library to allow you to make tabular data sortable by clicking on the headers.
It may or may not be the same codebase, but Plone has this out of the box (and has had for a year or so).