I've probably transgressed the rules of 10 Tenths in posting the same topic in two different places (currently as well in F1) However:-
In 2000, in every Grand Prix a podium position was filled by someone racing 10 years later. OK the persons involved are Michael Schumacher and Rubens Barrichello but this must be a unique piece of F1 history?
In the era when I grew up this would be the same as Fangio, Ascari, Farina, Hawthorn, Prince Bira etc appearing in the 1963 Grand Prix season alongside Jim Clark, Graham Hill, John Surtees etc.
Yes - I was fortunate enough to see Roy Salvadori (Crystal Palace 1963) who raced in the 1953 British Grand Prix. I also saw Jeff Gordon, Mark Martin and Jeff Burton (Nascar Phoenix 1997) still racing 13 years later - but things are a bit safer nowadays.