Anime First: The series was later adapted into a two-volume manga, which was less comedic and even more of a Mind Screw than the original series. An omnibus edition of the manga was released in 2012, featuring an additional story and lots of artwork and character designs.
Keep Circulating the Tapes: Not the case anymore, but the show fell into this in North America for a few years due to a combination of its continuing popularity and the licensor (Synch-Point) folding not long after releasing a complete boxset with additional extras. In the months before Funimation rescued the license, copies of the original DVDs (to say nothing of the boxset) were going on eBay for ridiculously high prices.
Network to the Rescue: Synch-Point went out of business, and for years, there were no DVDs after the initial print run of the box set. Luckily, Funimation decided to re-release the series on a single DVD and give it its first ever (American) Blu-ray release. Similarly, after Tokyopop shut down its American division, Dark Horse Comics released an omnibus edition of the manga.