I haven't really looked into personalizing my Google homepage.
But there's one personalization I would really like to be able to add : the English to Portuguese translation box from the language tools.
It should be easy, but it's not obvious how I might do this. Or how to find documentation for writing third-party modules.
Still, it's clear as I browse the increasing catalogue that the customized Google home is evolving into another platform. There are clocks and games and RSS feeds etc. And maybe something useful at some point.
Also, now that Google know the kinds of feeds we subscribe to on our homepage, can they use this to help rank the results from feed searches? (Except that the fact Google provide some defaults screws this up.)