Howard builds a machine which enables 2 people to simulate a human kiss.

Jerry is getting a new air conditioning unit. Elaine asks why, because he's never wanted air conditioning before. But Jerry's new girlfriend feels more comfortable in with air conditioning, so Jerry is getting one—his demand has increased.

When a product is in high demand, a manufacturer is obligated to charge a little more to pay back the investors who took a risk on the product. Watch Warren Buffett’s Secret Millionaires Club on the Kid Genius channel on Xfinity. Visit SMCKIDS.COM for webisodes, comics, games, and more!

Howard comes up with an idea for an app to solve differential equations.

Amy is mad at Sheldon, and he goes to the jewelry store with Penny to buy Amy something. Sheldon hints to the salesperson that diamonds are carbon just like charcoal, but it's only their molecular arrangement that makes them valuable. When the salesperson tells Sheldon that everything is on sale, Sheldon is suddenly more interested in a pocket watch he was previously considering.