When Lisa takes the phone and vows to tell professor Frink that he's won the Nobel Prize, she finishes the call with the words "Tack för att ni förärar vår stad". That is actually real Swedish, meaning "Thank you for honoring our town" (albeit with a questionable pronunciation).
Not only is the Homer as Grim Reaper plot lifted from Family Guy (1999), the writers also used the exact same joke in which a character mispronounces "wind" because they've only ever read the word in books.
The Simpsons is often credited as getting to all the ideas before other shows get a chance. However, in the segment "Reaper Madness" Homer becomes death, which had already been done by Family Guy (1999) in the episode Death Is a Bitch (2000) that aired three years prior to this one. Although in "Death is a Bitch", everyone else is unable to die because Death was incapacitated, not because he was killed by a bowling ball.
When Bart and Milhouse repeatedly change the sign outside town hall each iteration uses only the available letters from the original sign RECENT STRANGE EVENTS: NEVER EAT GREENS, TV TEENS GET ACNE, and GENT'S REAR: TEN CENTS.