Back during the Olden Times of EV (That would be before 1998), there were basically a series of plugins that each managed to redefine the genre and then got generally forgotten when people figured out how to cram better graphics in. They were, In order:
(ulr=http://www.geocities.com/TimesSquare/Arcade/4503/)Foundation(/url), EVGE, Final Battle, Pale.
Also, please don't write off Eye of Orion - it wasn't that good, in and of itself, but it was epic in scope and was the first real experiment in immersive mission writing.
The Frozen Heart was originaly written as an EV plugin, and is available in that format sans-quicktime movs. Regardless, it and Femme Fatale were pure awesomeness in a can.
There's a whole mountain of plugins that should really have been released, goddamit, but weren't. I can't name them all, but I'll point out Vorinth and Edge of Infinity for special note.
Then there's the ones that didn't get released (Got "Vorinthed"), and thank god they did - the public didnt' need to be subjected to something that awful. Prime among these would be Final Battle II: Xenocide (later on, just "Xenocide")
In the end, though, I have the salute Benjamin Singely's masterpiece, "Pale", as what has to be the best plugin of all time. It was genius.
-reg
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"Oh crap. I'm going to hell - I put the Bible next to Mein Kampf again."
-Her Holiness, Pope Jenne "Kirby" Hubbs