We'd like to have Ross Mathews' brain for a day, just to see what it's like to be so happy all the time. He was having a blast interviewing stars on the red carpet at the Oscars for 'The Tonight Show With Jay Leno' (weeknights, 11:35PM ET on NBC).

And the stars didn't quite know what to think of him either, or maybe they were just trying to think of something equally witty to say. The look on Robert Downey, Jr.'s face when Matthews suggested he play him in a movie was priceless.

Watch the video after the jump.We'd like to have Ross Mathews' brain for a day, just to see what it's like to be so happy all the time. He was having a blast interviewing stars on the red carpet at the Oscars for 'The Tonight Show With Jay Leno' (weeknights, 11:35PM ET on NBC). And the stars didn't quite know what to think of him either, or maybe they were just trying to think of something equally witty to say. The look on Robert Downey, Jr.'s face when Matthews suggested he play him in a movie was priceless.