Give lots of time for communing. Build time into the workday for people to hang out and just talk. Give your people permission to drop work and be with each other.
Have a lot of food around. We found last week that we couldn't eat at times, and then we would be ravenously hungry. Pizza out of the blue or midafternoon cookies help a lot.
Take care of yourself. Don't neglect yourself. Get sleep, get exercise, and make your own time for communing and reflection. It's a long-distance run, not a sprint. Conserve your energy.
As I read above, it all feels so "surface" given the scope of what has happened. I'm sure you've got many other insights. Check out the discussion board that is included in this My View. I (and all of the Forrester community) would love to hear your voice on this issue.
George