Umbrella Liability Policy?

Considering the litigious society we live in, and considering the liabilities that can come up concerning the use of a firearm, I'm thinking that an umbrella liability policy would be a good thing (like $500K to $1 million). Not only do we have to concern ourselves with lawsuits if we have to shoot someone (even if it is justified), we have to worry about any bullets that miss the target. Nobody, not even well trained police, can be 100% sure that every single round will be on-target. You might put 100% in the middle of your target at the range, but when things get crazy in a threatening scenario, your accuracy will vary. We might hit a car, an innocent by-stander that comes into the field of fire, or whatever/whoever. Even police agencies are regularly sued when officers are justified in the use of deadly force. So, us civilians are certainly a target for plaintiff attorneys if we are involved in a shooting.

Question: How many of the forum members have an umbrella liability policy, in addition to their personal liability coverage on their homeowners policy?