During the years when I was really into Martial Arts I went to many displays and tournaments , among some of the people I met before they were famous are :
Jean Claude Van Damme (in Belgium at a training seminar)
Dolf Lundgren (I saw him defend his world title twice and spoke to him at Bercy in France when he was passing on some expertise)
Rutger Hauer (when I lived in Holland I did a stint as a security adviser and was visiting Hillegom where all the Dutch TV progs are made and met a lot of Nederlandse sterren (Dutch stars))