For those that do not know about Pmw, here is an extract from the documentation. Pmw is a toolkit for building high-level compound widgets, or megawidgets, constructed using other widgets as component parts. It promotes consistent look and feel within and between graphical applications, is highly configurable to your needs and is easy to use. A library of flexible and extensible megawidgets built on the base classes, such as buttonboxes, notebooks, comboboxes, selection widgets, paned widgets, scrolled widgets and dialog windows. It also speeds up module loading time by only importing Pmw sub-modules when needed.
Full descriptions are also available for all the base classes and several other megawidget classes.
Descriptions of the other megawidgets will be released soon. A slick demonstration of the megawidgets. An interface to the BLT busy, graph and vector commands. The interface to Pmw megawidgets is similar to basic Tk widgets, so it is easy for developers to include both megawidgets and basic Tk widgets in their graphical applications. In addition, Pmw megawidgets may themselves be extended, using either inheritance or composition.