[development] Passing options to the front page

[Jeff Greenberg]

I'd like to have some dynamic theme changes to the front page based on 
items clicked on the front page.  What's the best way to do this? I know 
that ?page= is valid, as is ?q=, but am unsure how to add my own 
key/value and react to it. If it were another page I'd use a callback, 
but it being the front page seems to require a different approach.

Jeff