Ask HN: What can I sell in Times Square?

A friend and I are hackers who want to learn how to sell better. We live in NYC, and we thought a good way to learn would be to sell stuff in Times Square. So far our list includes: 1) Buy a cheap costume, and then charge people to take pictures with us, 2) Sell I <3 NYC t-shirts in different languages, 3) Sell roses. Any suggestions on what we could sell or thoughts about our project?