Damage to objects? Options

[sorcel]

Anyone have rules of thumb for damage to objects?

For example:

1. A sammy accidently drops his Ares Predator IV off a roof. What's left when it hits the 'crete? SR4 gives rules for falling damage, but nothing for the *amount* of damage an item can take.

2. A hacker is unhappily caught in the blast radius of a High Explosive Grenade. How might one figure the odds of the hacker's uber-expensive commlink being roasted in the blast? Obviously we have rules for calculating damage to the person, but what about damage to the gear that person is carrying?

3. An katana-wielding adept tries to chop his opponent's shotgun in half. How should the defender roll his defense? Reaction + Dodge? What if, instead of a shotgun, the defender was holding a petunia? In other words, how would object hardness play into the equation? Some sort of Armor rating, maybe?

Of course, there's also the possibility that all this stuff is in the book and I'm just not seeing it... in which case, maybe point me to a page, or even a section?

Thanks!

-S