“Next, we only sell the outside of bagels!”

“Seinfeld” will run in syndication until the end of time. And, when the aliens sift through what’s left of our civilization, “yada yada yada” will be remembered as holy writ. With Jerry Seinfeld in town, we look at the show’s jokes that haven’t aged as well.

Muffin Tops
In “The Muffin Tops,” Elaine comes up with a business idea: sell only the tops of muffins, since the stumps suck. The idea takes off, but the store has to deal with topless remainders. This problem is made irrelevant by the muffin-top pan, available at stores near you ($16, Macy’s).

In “The Sponge,” Elaine’s favored form of birth control — the Today sponge — is in limited supply since being pulled from the market (a real event). So she has to be, um, choosy. But the device came back in 2009 and is easily available in drugstores and on Amazon.

Kramer’s phone number is similar to Moviefone’s, and hilarity ensues in “The Pool Guy.” See, we used to dial this number and a guy with a really engaging voice would tell us movie times. To revisit this part of our history, call 202-333-3456.

Answering Machine Tapes
After George leaves bizarre messages on a date’s answering machine, he and Jerry team up to retrieve them — on a tape! — in “The Phone Message.” We also used to use tapes to record TV shows and to profess our love to the boy from algebra class.

Kennedy Center, 2700 F St. NW; Fri., 7 p.m. and Sat., 7 & 9:30 p.m., sold out; 202-467-4600. (Foggy Bottom)