The disbelieving clerk Ash is explaining his adventure to in the S-Mart ending is Ted Raimi, who can also be seen in the crowd below the castle battlements receiving Ash's pep-talk just before the battle with Bad Ash's Army of Darkness. Ted is director Sam Raimi's brother--and is best known for his part as Joxer in the Hercules and Xena TV shows (of which brother Sam was executive producer) where he again worked with Bruce Campbell.

Ash's car has appeaered in most of Sam Raimi's movies. Look for it in Spiderman and Darkman.

AOD has 2 different endings, the one where he goes back and fights the zombie lady in S-mart, and the original one where he swallows too much juice and ends up in an apocalyptic future, they wanted to use the original ending but Universal wanted a more audience friendly ending, and they didn't want Ash to be such a anti hero so they changed and deleted a few other scenes. They released the original version to some countries.

The Magic words that Ash said (Klaatu, Barada, Nikto) are also the names of three aliens on Jabba the Hutt's barge in Return of the Jedi, which in turn took the words from The Day the Earth Stood Still.

When Ash calls Wiseman Joe "spinach chin," it's a reference to the classic Three Stooges short Malice in the Palace (1949), in which Moe Howard calls a man with a long beard "spinach chin."

When Ash opens his trunk to get out some useful items, there is a Fangoria magazine and the cover is for Army of Darkness.

Contrary to popular belief, the items we see in Ash's car (the 'Fangoria' magazine, the Coca Cola bottle etc.) are not product placements. Sam Raimi actually had all that stuff in the trunk when the car was brought in for filming and never bothered to clean it out.

Army of Darkness is called "Captain Supermarket" in France.

Bruce Campbell says that in order to make it appear that the chainsaw was always running, tobacco smoke was pumped through a tube that was slid up his right pant leg, up his shirt, and into the chainsaw.

Ash speaks the words, Klaatu Varata Niktu, this was paying homage to a film called The Day The Earth Stood Still.  The words in that were Klaatu Barada Nikto,(only slightly different), they are spoken by one of the humans (at the request of Klaatu) to Gort (Klaatu's robot) after suffering a potentially fatal injury at the hands of humans, to prevent Gort from destroying the earth. The tenuous link, therefore, is that this phrase must be spoken precisely to prevent the end of the world in both films...