For baseball, the 1935 Pebble Beach Clothiers Lefty O'Doul. I'd been collecting O'Doul pieces for years, and it took me until the 2006 National to find one of these. Mark Macrae, one of our members, had 2 of them at the show. Interesting story on this one. The back has a handwritten name ___ Dempsey. Turns out this card was once owned by Con Dempsey, a SF native who ended up playing in the PCL and in MLB. He has a card in the 1952 Topps set.
And for a boxer, this 1904 Jeffries-Munroe 2-sided Sporting Life cabinet card. Only one specimen is known. I'd seen it years ago in the Dreier collection and as a Jeffries collector [he is from Burbank] when it came up for auction I had to have it:
