There is a new edition of Wine Town Firenze happening this May 17th and 18th. We have written about this event before, but this edition seems very organized, and their website is up to date, with maps and information (unfortunately, it seems to be only in Italian at the moment however).
This event works with a charged card (you buy an initial card for 15 euro that has 5 points on it) and you can refill the card as needed. Some wineries charge several points for their wines, but there are plenty that are a single point or two. It is also usually more than just a taste - it is a small glass of wine to enjoy at the various events and "palazzi" - where there is usually music and some other types of performances going on.
And of course, there is always some kind of food to be found! Here are some photos from past editions: