I vaguely remember psionics (at least in 2nd edition). Looked like an ok alternative to regular magic...if you removed regular D&D magic first. If I recall, they didn't play very well together.
In my PW (and the gameworld it's based on), there have never been, nor will there ever be, psionics. I've allowed several "psionicist" characters (because I don't really want to limit the roleplay too much)...they can just play as sorcerers and call it "psionics".
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