Members of the 1908 Chicago Nationals - almost completed
My son, also a member of the class of '08 (2008, that is)
Still need Del Howard, Andy Coakley & Vin Campbell on a period-era card to get everyone. Bill Mack pitched the only two games of his career for the team, and Karl Spongberg made his one and only appearance in the majors as well. Neither, as far as I can determine, ever appeared on a baseball card.
Interesting tidbit about Spongberg & Mack: Both had career batting averages of .667 (2-3).