Casino Royale (1967)
The 1967 Casino Royale was a spoof not only of James Bond and other spy movies, but of pop culture in general. Seriously, it was the Jason Friedberg movie of its day, throwing every then-contemporary pop culture reference it could think of into the pot, from Woody Allen (who also starred in and directed a piece of it) to What's New Pussycat? (which starred Casino Royale cast member Peter Sellers) to Westerns to - of course - Frankenstein. It's very much an everything-plus-the-kitchen-sink movie in the tradition of Hellzapoppin' and features another Universal-ripoff Monster for ease of recognition. Mostly, this version is remarkable because it's played by David "Darth Vader" Prowse.
Also in the tradition of Hellzapoppin', here's the completely nutso ending even though it doesn't have the Monster in it.
And just because it's hilarious and awesome: a fan trailer that makes the movie look infinitely better then it really is.
Mad Monster Party? (1967)
I don't know how I got through childhood without knowing about this Rankin Bass masterpiece, but I didn't discover it until I was all grown up. Boris Karloff is the voice of a Dr Frankenstein who wants to retire from his position as leader of all monsters everywhere. Unwilling to leave a power vacuum, he calls everyone together to Monster Island (not that one) so that he can announce his successor: his nephew; mild-mannered soda jerk Felix Flankin. The other monsters are of course unhappy about that, especially the Baron's hot lab assistant Francesca, so they split into factions and shaky alliances in order to bump off Felix and claim the leadership position. The monsters include Dracula, a werewolf, a Creature from the Black Lagoon-type sea monster, the Invisible Man, the Hunchback of Notre Dame, Dr Jekyll/Mr Hyde, the Mummy, a Peter Lorre-like ghoul, and of course the Frankenstein Monster (called "Fang," for some reason) and his Mate (voiced - and looking like - Phyllis Diller).
With a script and character designs by Mad Magazine's Harvey Kurtzman and Jack Davis, the hour-and-a-half movie is very funny and looks great. It's easily in the top five specials Rankin-Bass ever produced. Davis' creatures are all a mixture of his distinctive style and the classic film versions everyone's familiar with, including Fang.
Apparently there was also a cartoon (very loose) sequel in 1972 called Mad, Mad, Mad Monsters, but probably the less said about that the better.