Heptathletes have the chance to become the new Olympic heptathlon champion every 4 years. The current champion being Natalya Dobrynska. The heptathlon Olympic record holder is Jackie Joyner-Kersee.
Ashton Eaton holds the current world record in heptathlon.
Usain Bolt is the current world record holder for the 100 meter dash
Before the current record holder, Edwards, was Willie Banks.
There have been many heptathletes. There is the world/olympic record holder Jackie Joyner-Kersee, there is also the british record holder Denise Lewis. Most of the well known heptathletes are European although that is not always the case, Hyleas Fountain of the United States of America is a a also a well know heptathlete.
As of May 2014, Jan _elezn_ is still the current Olympic record holder for the men's javelin. He became the record holder in April 1986.
Current record holder for the Olympics is Almuneda Cid, having participated in the Olympics for Rhythmic Gymnastics 4 times.
I'm not sure if this is the only event, but Jonathan Edwards of Great Britain is the world record holder in the triple jump with a jump of 18.29 meters.