I remember back in '76 a friend of a friend in college showing us some of his fancy bike stuff including a Ti crank spindle. It was the first Ti I ever saw and got to heft. It was amazingly light. Back then they were breaking so fell into disfavor. I'm sure all that is ironed out now...though a big fat thin-walled Al tube like in modern GXP and press-fit systems is probably a superior design, IMO.

edit: senior moment...upon reflection I realized it was in 1972, not '76.