Adorable gift shop on State. They sell a variety of prints, buttons, cards, crafting supplies, jewelry, tote bags - you name it, they've got it and it's probably cute and/or funny to boot. I also like that they have a lot of political-themed buttons, posters, and jewelry; it adds spark and personality to an already lovely gift shop.
Additionally, the customer service is great here. They were once out of a print I wanted to buy but they offered to take my number and call me when they had it back in stock. I promptly received a call about a week later.
If you need a card for a special occasion or a cute Madison-themed gift, I would definitely check out Anthology.