We were both fledgling sf writers at the time, each of us with a few short story sales under our belt. When we met, we did what fledgling writers often did in those days: we decided to write a story together. We actually left the Playboy Club atop the con hotel to begin it. (Probably just as well. Beers were real expensive up there, I recall -- a whole quarter).
We only wrote a few pages at the con, but we kept at it afterwards, sending the manuscript back and forth, until it was done. "Men of Greywater Station," we called it. Pretty much everybody in the field rejected it until it finally got to the lowest paying magazine, where it was purchased and, finally, published. The readers seemed to like it well enough.
Howard and I remain close friends to this day, but we never collaborated again. Our styles were just too different. But it was fun doing it once.
And now, all these years later, it's been done as a podcast by Starship Sofa:
Check it out for yourself. It's free, and I thought they did a nice job.