I'll go first, with a few memorable pilots, in no particular order;
My friend Bill Loverseed, ex RAF and Red Arrows. He was an incredible mentor, and a kind person. In my opinion, he was a nice person always looking for somewhere to help. I'd flown with him a few times as a passenger while I worked for his employer at the time, deHavilland Canada. I flew over to England as one of his passengers in the Buffalo in 1984, and was kindly invited to ride jump seat during the demonstration flight at Farnborough. Two days later, his demo flight in the same plane did not have the intended outcome. No one hurt, just bent metal. Bill went on to private ferry flying, and I flew all over the world learning with him, the types and experiences too numerable to mention. He would regale me with stories of RAF and Red Arrows flying, and soem entertaining demonstration flying with deHavilland airplanes. I learned a tremendous amount from him during the ten or so years I spend sharing a friendship with him, right down to a number of sailing outings in Lake Ontario, and later Bosham Estuary. we lost Bill, and another friend Mic Saunders, in November 1998, in the crash of a Dash 7. But I keep thinking of Bill.
Vic S. a kind and wise helicopter pilot, who used to let me fly pipeline patrol with him. He gave me his new, but unused helmet while he ordered a better one. While awaiting it's delivery, flew a patrol, flew into electrical wires, and was lost. I don't think the helmet would have saved him, but I think of it when I wear it.
Rick V. Owned the Cessna Service Center local to me, and gave me wonderful opportunities to maintenance check fly different types, test modifications, and ferry parts and airplanes. Rick got too complacent with a stock C 150 one day, and was killed on impact. In my capacity as a local volunteer firefighter, I was called to the crash, and had to help lift him out of the wreck. Happily for him, he would have had about five seconds of "Oh S..." and then no suffering, and I remember all the things he taught me - a couple of do not do this. After his accident, I stopped doing a few silly things that I also used to do in 150's!
And Rob, who died flying a Cessna 207 I was responsible for. Again, I learned more from Rob, what not to do, and to what to do, but he was a nice fellow. I have a single distinct memory of Rob, he bought on of the first Ipods, and put all his music on it. He told me that he just set it to shuffle, and let it play. he'd loaded all the music he liked, so let it play through randomly. So, silly as it is, when I play my Ipod, I think of Rob.
I have lost more friends than these fine fellows, but on to other posters with memories they would like to share....