I'm sure everyone's all cranking up and donating (aren't you?)
Here are some useful Katrina links:
Check on the safety of friends and family at the National Institute for Urban Search & Rescue's Missing Persons Center for Hurricane Katrina. http://www.niusr.org
The Red Cross site keeps getting Slashdotted, but there are plenty of other places to donate. FEMA is a good place to start, plus they're hosting lots of good information. http://www.fema.gov
Lastly, if you work for an organization that falls under "critical infrastructure" then I encourage you to join the Northwest Warning, Alert & Response Network. Yeah, there's a tiny bit of a background check , but it's a good resource for contigency planning. http://www.nwwarn.gov/