Read story here. I quite liked him in 10 Things I Hate About You. Didn't watch Brokeback Mountain though as it's not my type of movie but may his soul rest in peace, Amen.
Wikipedia: Heath Ledger
Also, R.I.P : Sir Edmund Hillary (July 20, 1919 - January 11, 2008)
He and Tenzing Norgay became the first climbers to have reached the top of Mount Everest.
Wikipedia: Edmund Hillary