The ending credits open with "In Memory of Larry Einhorn"; Larry Einhorn was the recently deceased father of Randall Einhorn, who directed several episodes of the series.
When Donna claims she got her earrings at a mall in Philadelphia, Kelly asks if it was at Franklin Mills, King of Prussia, or Springfield, which are all real malls in and around Philadelphia.
The Morse code in the cold open is mostly gibberish, mainly from Jim.