Guru Lou
Lou's a smart-alek scientist/con-artist, always trying to test out new inventions and discoveries.  However, not a whole lot seems to work with this guy.  Fortunately, he has a few guinea pigs to test his inventions on: the Pizza Cats (that elixir was especially hilarious).  Sad part is, for some reason, Lou's existence is important to Speedy.  Thus, the Pizza Cat is always coming back to him to see if he has something working that'll help him against the forces of evil (bad move most of the time).
Lou is credited to have "made" the Supreme Catatonic, the Cats' crime-fighting robot.  However, from the mouth of Jerry Atrick, we now know that he didn't build the Catatonic at all....he discovered it (it was built by a different society centuries before).