Jerry and Elaine back together again!

Seinfeld costars Jerry Seinfeld, 61, and Julia Louis-Dreyfus reunited last night to bid David Letterman farewell during the Late Show host's final episode on Wednesday, May 20.

"Last night backstage @letterman @JerrySeinfeld #thanksdave," the 54-year-old actress captioned a fun photo of her posing with the comedian.

Ever wonder what the rest of the Seinfeld cast has been up to since their show about nothing went off the air 17 years ago? Click through the gallery below to see!