The Anime d20 SRD brought some interesting changes to the original 3e d20 SRD. Aside from BESM d20, which obviously isn't a derivative of itself, which games have made use of the Anime d20 SRD - in particular the modifications to the base classes, moreso than the new classes that were introduced.
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Guardians of Order used it for a variety of subsequent games, like Slayers d20, Hellsing, Trigun, and Uresia. In terms of games from other people, the field is pretty small. Arakos: The Eighth Age from Battlefield Press is the only one currently available. Seraphim Guard used it for Heroic Ages III, Banzai! and Heroes of the Floating Worlds - this was long ago and I'm not sure if those games ever saw release.
Reference: RPG.net list of Anime d20 products (Omits Slayers for some reason)