My friends at Optimal Usability have released their brand-spanking new card sorting tool into beta release (it's free until August).

Their tool, called OptimalSort, caters for open and closed card sorts. The sorting interface is a spatial drag-and-drop.

The thing I like best (and I will fully disclose that I was involved in this, so I should like it) is the analysis options. No stinkin dendrograms here, but lists of category names, detailed participant results and lots of ways to explore the data.

Go try OptimalSort.