A late, and perhaps controversial, entry into this season’s frozen treats giveaways, Dippin’ Dots is celebrating their 20th anniversary by giving customers a free cup of their curious beads of ice cream from 4 p.m. to close today. Invented in 1988, Dippin’ Dots are touted as “scientifically advanced” due to their cryogenic-freezing process, earning them the title of “Ice Cream of the Future.” They are also releasing a new, yet unsurprising, flavor: Birthday Cake. Unfortunately,…