Keep Circulating the Tapes: Ever wanted to get it after 2004? New copies haven't been released since then, and it is pretty rare to find it (at least on DVD, which costs around 50 bucks, the VHS is considerably cheaper, selling at around 15 dollars).
Name's the Same: Pajama Sam also has a place called the Land of Darkness. (Bizarrely, Sonic the Hedgehog: The Movie's initial Japanese release was on the same day that Pajama Sam in No Need To Hide When It's Dark Outside was revealed at E3.)
Screwed by the Lawyers: Because of all the red tape considering copyright, no characters outside the main Sonic cast from the OVA are allowed to be used outside the anime in any Sonic media. Even if it's just a little reference such as Knuckles cowboy hat, which the Archie comics did as a little Easter Egg in one of their issues. Sega ended up chewing them out for doing so when they found out.