yesterday i stumbled upon a cool extension for Firefox / Flock browsers to display microformats contained inside a page:

tails firefox extension (Firefox 1.4+, Flock 0.7+)
flocktails (Flock 0.5.14+, Flock 0.7)

the plugin scans your currently viewed page in your browser and displays a small, green icon () in the bottom right of your browser if it has found any of the supported microformats inside the page. If you then click this icon you get a topbar in Flock or a ovelay in Firefox which lists all of the microformat elements it has found:

to see it in action try this link