Bean's goofiness comes dangerously close to completely ruining David's life after he accidentally destroys the portrait of Whistler's Mother. When he realizes how much trouble he's caused his new pal, Bean shows a stunning level of intelligence and competence in fixing the problem when he turns a poster reprint into a dead ringer for the original painting (which he kept and took home with him to England). His heist of the museum is fantastic, making the end all the funnier for the Mood Whiplash.
His effort in slowly turning an improvised speech about the importance of Whistler's Mother as a piece of art from a set of bungling stammering into an analysis of the worth of familial love.
He manages to save Detective Brutus's life by accidentally removing a bullet from his abdomen, without using any surgical appliances, while searching for a peanut M&M he dropped into the open wound. He puts the bullet back in the first time around, unsure of whether it belongs there or not.
He also wakes David's daughter Jennifer from her semi-coma, without inflicting any brain damage. Also by accident.
As mentioned in the (sort-of) novelisation, Mr Bean is capable of getting into anyone's house (in this case David's) due to his realisation that "If it's a choice between hiding your emergency key under a brick or under Kermit the Frog, which would you choose? Well OBVIOUSLY!" He keeps his own emergency key under a frog statue as well.