I'm keeping this within just the first four seasons as (to my knowledge) that's all you've seen.

I didn't see anything for seasons one and two. However...

Season Three Bloopers
https://www.youtube.com/watch?v=vhKeN2B6uqA

Season Four Bloopers
https://www.youtube.com/watch?v=XQpEv0NTX7k

There's bloopers from the later seasons too. These are hilarious.

Cool - I'll check them out - Thanks Adam. Just started S5 - just finished watching the ep where Brian broke his butt lol