All:Thanks for all the answers and suggestions. Due to popular demand, I've posted my sophomoric Ruby code for Word Clock to the ShoeBox:
http://the-shoebox.org/apps/150
For the Shoes experts reading this, what I *think* I want is an
abstraction where I can pre-generate all the <span> elements, and use
<element>.replace to swap in highlighted and un-highlighted versions
of the text. That seems tantamount to computing things off-screen,
and I haven't figured out how to do that yet.
Enjoy. - Rob
