Florence is home to some of the most beautiful storefronts I've seen: they're colorful, decadent, and it's easy to lose track of time just window-shopping. It's how I found my discounted Hunters, my favorite gelateria, and my favorite stationary in the entire world. (I may have brought home one too many sheets...)
I'm usually weary of the San Lorenzo market since I'm still working on my haggling skills-- but the colorful leather and scarves throughout the market are really lovely. If you go, never settle for the listed price. I'm usually shy about doing this in Italian but it's how I bought myself a leather belt and green wallet for my mom for 25 euro altogether.
Perhaps the most decadent of all decadent shop displays are those on the Ponte Vecchio-- the oldest bridge in Europe. The bridge used to be lined with butchers until Medicis wanted to make the bridge more prestigious-- then they prohibited butcher shops and goldsmiths took their places.
Now it's got beautiful (and super expensive) jewelry in each of its windows. Most people admire the gold and jewels, but the coral and cameo jewelry are my favorites. The coral is just simple and classic, while the cameos are elegant and remind me of my Classics major.
Going back and finding my own little treasure from the Ponte Vecchio is the newest addition to my list.