My commando gear
Apple MacBook Air
I love Apple's hardware for it's stability and it's resilience. I love OS X because while it has a beautiful and very usable GUI, it takes only one button to reach into its foundations (Terminal.app is on F2 for me), where I can summon the full power of unix to get things done effectively.
Spare: Another notebook with Lubuntu.
35MB Internet connection
My main pipe. Quite reliable. I love it.
Spare: Fast LTS mobile net.
iPhone & iPad
Surprisingly, the iPhone is much closer to a notebook than to a phone. Not only I have full web access from everywhere, I can also read and reply email. There are tools for monitoring servers and even for SSH-ing into them to start or check on jobs and scripts.
Spare: An Android phone.
Paper notebook
Often the right thing to do in solving a problem is to put a little distance between it and us. Having a bird's eye view of the bigger picture usually offers solutions that were invisible earlier.
At times like this it's good to go to a park or a teahouse armed only with some papers and a pen, and let the mind do what it does best. Scribbling. Brainstorming. Drawing mock-ups. Sketching. Spilling the subconscious onto a paper. Then going back to the computer, and writing it.
Spare: Note-taking and mind-mapping applications on the iPad. :)