The calendar widget is handy, but deserves to look better. By adding support for jQuery UI standard theme set up, you can add a few default themes to choose from. Users can also make their own themes with a few clicks using the jQuery Themeroller.
The Search Autocomplete is one example of how handy this is. When implemented, it takes just one click to select a theme that makes the calendar look for example like this: http://2.bp.blogspot.com/_SPbUIiu4sfA/Sn7XP4QC2SI/AAAAAAAACAg/Q9rZReomeAE/s320/datepicker.png