Unless you're talking Tk or some other window manager interface, you can't do UI like that with Perl...? I'm sure you know this so maybe I don't understand the question.
If you're looking for the most Desktop-like JS lib for web stuff, it's ExtJS. It was a fork from YUI originally, IIRC, and it's feature rich if a little on the large side. There are two examples of using it with Cat here: Getting started with ExtJS screen library and Catalyst with Ext+Ajax: Editable Data Grids.
FWIW, there are a couple of really hot jQuery (my pet lib) plugins that do some of the same things (like live data tables and dojo-style comboboxes). Though jQuery plays nicely with ExtJS and other libs so you can mix and match.
(update: downcased k in Tk; linked jQuery.)