Here is an event I have just heard about that looks very interesting. My husband and I will be attending.
The WineTown event is where you can taste many different wines from the region. You purchase a card with 10 euros credit on it and receive a glass for the tastings. There is also a 30 euro card available that allows you not only to taste the fabulous wines but also to gain entry into participating museums.
So if you are in Florence this weekend this is a must see event.