The fancy antique bottle which Jeannie called home was actually a decorative Jim Beam liquor decanter, which originally contained "Beam's Choice" Kentucky Straight Bourbon Whiskey. The bottle had been decorated and painted with gold leaf by one of the show's art department employees.
Jeannie's diabolical look-alike sister, "Jeannie II," a brunette with a green harem dress, was created by a former "Bewitched (1964)" writer, James S. Henerson. He was fired from "Bewitched" when it was discovered he was writing for both shows at the same time.
The Nelson home still stands on the "Warner Brothers" Ranch in Burbank, CA, where it has a new role as the Ranch Operations office. Aside from minor cosmetic changes, the house remains almost exactly the same after nearly 50 years. Update - Oct. 2023: unfortunately, the Nelson home along with all the other historic structures on the Warner Ranch backlot have been demolished to make room for sixteen new sound stages.
Barbara Eden personally selected the pink/maroon color combination of Jeannie's harem outfit. Pink symbolizes the playful, girlish aspects of her personality, while maroon symbolizes the fiery, headstrong aspects of her personality. Eden also selected the purple trim of her bottle.
Larry Hagman could be so hard to work with that the producers seriously considered replacing him with another actor. Darren McGavin was at the top of the list for Hagman's replacement. They even wrote out a story with Tony losing Jeannie and McGavin finding her. However, studio executives liked Hagman much more than the producers did.