Here's one that literally slipped right through the cracks.
While most of fandom knows Spider-Man returned to network television with the Amazing Friends series on NBC in 1981, a syndicated solo series that launched at the same time wasn't picked up in a lot of markets, including mine. For that reason, the 1981 Spider-Man solo series lasted just one season, while Amazing Friends hung on for a total of 3 seasons before being cancelled, then returning a decade later as part of the Marvel Action Universe anthology series in reruns.
I rented a VHS compilation of this series once. Just one episode, if memory serves me correctly, with Dr. Doom the villain du jour. What was interesting was that it sounded like long time Sunn Classic Pictures announcer Brad Crandall as Dr. Doom, which I believe is Crandall's only cartoon credit of note.
DirRudy uploaded the open to YouTube. A couple of frames also appear in the Amazing Friends open, and the title portion was modified for Amazing Friends.
I don't think the series has been collected on DVD as yet, but Disney, the current rights holder, would be wise to consider doing so in light of Spidey's 50th anniversary.