As brilliant as Firebug is, I would consider switching my JavaScript debugging to Chrome if I could figure out how to get it to always re-download styles and images on every visit to the page?
When I'm testing a page in Firefox, it always gets the latest version.
But in Chrome I often end up scratching my head over something that turns out to be a simple issue of the browser caching some earlier styles or images.
Is there a way to configure Chrome to cache less while you're developing?
I often use private browsing mode for this - it prevents caching of the stylesheets or scripts.
EDIT:
Another really easy way to do this in Chrome now is to go into the Chrome Developer Tools, click the settings gear (bottom right), and then check "Disable cache." See https://stackoverflow.com/a/7000899/4570.