Mac chasing after Guy when he lied to Martin about passing his exams. Since Mac is usually an easy-going guy, it's extremely satisfying to watch him kick Guy's ass, especially considering how horrible Guy is to Martin.
Angela and Caroline have a fight because Angela thinks Caroline is wearing her underwear. Eventually it turns out Caroline is innocent, and she says this gem of a line when walking off, which is especially satisfying considering how undermining Angela is towards her;
Caroline: Why don't you go ask your boyfriend? He looks like the type to wear girl's pants. *snaps the waistline of her own underwear*
Statham seducing Joanna with ping pong balls.
Martin punching a chav in the face to impress and win back Karen.
One episode with Alan annoying the HR staff, Rachel suggests they have a kiss...then staples Alan's tie to the desk, and gets Joanna to kick him out.