"I think the Uni-Ball Micro 0.5 pen is the best pen overall. But the Muji 0.36 or 0.37 in dark blue ink is a very nice pen for other reasons. So those are the two I would use," Altman said.

The OpenAI chief said he uses pens from Uni-Ball and Muji to jot things down. OpenAI CEO Sam Altman likes to take notes the old-fashioned way — using pen and paper. Altman was speaking to writer ...