Picked up a couple of rules from Wed night game.
Penetrating Hits 40k6 pg 74
If a penetrating hit was scored, the vehicle not only loses 1 Hull Point, but also suffers additional damage.
Context: Black Templar Dreadnought was shooting at Ravager and scored a Crew Stunned result. Since I haven't used vehicles much in 6th ed this was something new for me. Thought it was just glances. Nope, Bryan taught me this. P.S. This one made me feel really foolish.
Grenades; Vehicles and Monstrous Creatures 40k6 pg 61
A model can use such a grenade as a Melee weapon, but can only ever make one attack, regardless of the number of Attacks in its profile or any bonuses. Different grenades have different profiles when used in this manner, as explained below.
Context: Vect was assaulting a Dreadnought. That is when Bryan reminded me about only using one grenade in H2H, hand-to-hand.