I got to spend time and dinners with him at several San Diego Cons, and he once visited Acme Comics when I was the manager, and we exchanged friendly barbs the whole time. A great talent. And he was a pipe smoker.
Harlan was unique. I never met him, but he has been a presence in my reading and viewing habits for decades. From prose, to Star Trek, to comics, he always managed to inspire and frighten me.
Yup.
He got most of his pipes from Barry Levin, in fact---the guy who popularized/invented "estate pipe" marketing---and they were friends. He'd often send marked-up galley proofs, signed first editions of books, and so forth to Barry as gifts. Famous writer souvenir stuff.
Mean as a snake to deal with in a professional sense, but quite funny and charming to his friends.
I had nothing but great experiences with Harlan. I know a lot about the dark side of him, and he could be very difficult. But, I used to throw barbs his way, and he'd throw them back in fun. But, then again, he liked me.
He received the full treatment in NYTimes. Much respected for his prodigious output. Apparently he could be a tough customer, not famous for his gentle nature. You really have to take a vow to write genre fiction, sci fi in this case. It requires as much craft to master a genre as it does to write to your own muse your own way, which you end up doing anyway. He got it done. RIP.