I went to Hongdae again today with the purpose of going to At Corner, a vintage themed cafe with an outdoor terrace (again, rare in Seoul). There's not a lot of seating at this cafe, which is surprising because it's got such a large space. Half of the space is a shop that sells little knick-knacks, tea towels, and the like. I even saw vintage telephones and an outdated computer. I think half of the seating area is reserved for smokers, so allergy sufferers beware.
The menu is pretty consistent with other cafes with hand drip coffees ranging from 4,500 to 6,000 for iced coffee. (I have no idea why iced coffee is so expensive in Korea. This baffles me. Truly.) I've seen them offer desserts on other blogs, but I didn't get any today.
How to get there: Get off at Sangsu Station (상수역) and leave exit #1. Take a right after climbing the stairs, and backtrack to the street that faces the back of the exit. You should see a florist shop across the street. Walk straight for a block, and you'll find At Corner on your left.