The easy thing to do is just see the shows featuring him and Nimoy together. I've only been to one con, but that was the one I saw. Priceless. Nimoy playing the straight man to Shatner's (apparently) a little inebriated self. I think the best part was when Shatner seemed to forget he had done a Futurama episode and Nimoy is whispering to him "You remember...."