Whenever Timmy does the opposite of what his parents say while the wish is in effect, the poof cloud says FOOP. Foop would later be the name of Poof's Anti-Fairy counterpart.
Mr. Crocker switches jobs and becomes a door-to-door ham salesman, and then a tour guide, in order to avoid Nega-Timmy. Even though fairy godparents were responsible for him becoming evil.
This episode (along with its partner episode) air very rarely in the United States during reruns for unknown reasons.
Wanda's quote "What's the worst that can happen?" is very similar to Timmy's catchphrase "What could possibly go wrong?".
Cosmo, Mr. Turner, Crocker's mother, and Timmy are revealed to wear makeup and said to look terrible without it.
While this episode is included on the season 5 DVD and is considered apart of that season, several sources, such as Netflix, consider this episode and it's partner, Love at First Height, a part of Season 4.
Adding to the confusion, these were the only episodes in the season besides You Doo/Just Desserts! that were produced in 2003, the same year most of season 4 was in production.