So while the fan mail kept mounting, I began to get calls from different organizations, all asking me to make public appearances."Great!" I thought, and accepted every offer I could. One call came from Medford, Oregon, inviting me to be grand marshal of the annual Pear Blossom Festival Parade in April 1967.

(...)

And when I agreed to go to Medford, Oregon, I decided to go in costume as Mr. Spock, as the parade organizers requested.
I never made that mistake again.
The parade went smoothly enough. I was very grateful to see the huge turnout—the largest in the festival's history—and although it was rather Strange to be in costume as Spock while smiling and waving as Leonard Nimoy in the back of a convertible, I enjoyed myself a great deal along the parade route.
The problem came after, when I was taken to a nearby park. A table was set up an the bandstand so that I could sign autographs. But instead of the hundreds I'd hoped to see, there were thousands of people there. They surged forward so quickly that I was terrified someone would be crushed to death; and then they started pressing against the bandstand so hard it began to sway beneath my feet! The people with me soon realized we were in trouble. Fortunately, the local police came to the rescue and pulled me through the throng!
The incident became a media event, and no one was more surprised than I. Later that afternoon, as I was contemplating what had happened in the relative safety of my hotel room, I got a phone call from the head of NBC's promotion department, who said,"From hereon out, we'll make sure you have security."
So, as I said, I made sure never to appear publicly again in Vulcan guise. But the crowds still kept coming.

Last March, Nimoy was guest of honor in Washington at a meeting of the National Space Club, which includes top men in the Nation's space program. "At first I felt somewhat ill at ease," he says. "As an actor in a TV drama, I had no way of knowing what the attitude of the scientific community toward our show would be. But I don't overstate the fact when I say that the interest in the show is so intense that it would almost seem they feel we are a dramatization of the future of their space program, and they have completely taken us to their hearts."

One person at the meeting told him that "Cape Kennedy practically shuts down when Star Trek is on."

(See interviews: 'Star Trek' Wins the Ricky Schwartz Award, 1967)