Michael Barnett has been writing a compelling, disturbing, and deeply practical blog from the frontlines in New Orleans. Here's a sample from last night:

The situation for the [New Orleans Police Department] is critical. This is firsthand information I have from an NOPD officer we're giving shelter to. Their command and control infrastructure is shot. They have limited to no communication whatsoever. He didn't even know the city was under martial law until we told him! His precinct (5th Precinct) is under water! UNDER WATER -- every vehicle under water. They had to commander moving trucks like Ryder and UHaul to get around. The coroner's office is shut down so bodies are being covered in leaves at best or left where they lie at worst.

They don't even know their own rules of engagement. He says the force is impotent right now. They have no idea what's going on, no coordination, virtually no comms, etc. the National Guard is gonna air drop a radio system for them with 200 radios? They are getting very little direction.

Meanwhile, The New York Times offers a lesson in the value of gun ownership:

Paul Cosma, 47, who owns a nearby auto shop, stood outside it along with a reporter and photographer he was taking around the neighborhood. He had pistols on both hips.

Suddenly, he stepped forward toward a trio of young men and grabbed a pair of rusty bolt cutters out of the hands of one of them. The young man pulled back, glaring.

Mr. Cosma, never claiming any official status, eventually jerked the bolt cutters away, saying, "You don't need these."

The young man and his friends left, continuing the glare. A few minutes later, they returned and mouthed quiet oaths at Mr. Cosma, and his friend Art DePodesta, an Army veteran, who was carrying a shotgun and a pistol.

Mr. Cosma stared back, saying nothing. Between the two sides, a steady trickle of looters came and went, barely giving any of them a look.

In Slate, Ari Kelman explains why so much of New Orleans was built below sea level.

Craig's List is helping Katrina's victims find housing. So is MoveOn.org.

And here, one more time, is Glenn Reynolds' list of flood aid charities.