That was over 13 years ago in 2008.
Today he is 56, and has starred in 100 movies in total, 35 since Tropic Thunder was released.
In Tropic Thunder, I think Robert Downey Jr. looks:
Tropic Thunder scores 6.5 out of 10 on The Movie Database.
Robert Downey Jr.'s first acting role was as 'Puppy' in Pound, released in 1970 when he was 5.