I was watching this David letterman episode where he interviews charlie sheen and charlie says ... David no one has a job like you, nobody can be like you I am just dropping paint off the roof.
I am paraphrasing but here's the video around 1:30
Letterman actually says "I'm dropping paint off a roof." He's trivializing his own work in a humorous way, in response to Sheen saying that nobody is as powerful as he (Letterman) is.
David Letterman had a running gag called "dropping stuff off of a 5-story tower" back in the 80's. He's probably referring to this. I couldn't find one with paint, but here's one example:
It would be fun to watch a can of paint. :)
Charlie Sheen is saying something like, No one has the same verbal impact as Letterman.
Letterman is replying with false modestly, "Me, I'm just throwing paint off the roof" (throwing random thoughts around).