I don't really have an office that I work from on a daily basis. I'm normally either working onsite with a client most of the time, or if I'm not onsite I usually prefer to work from my local independent coffee shop or Starbucks if I need an office that's "open late".
When I'm working onsite with a client though I'm almost always packing in a Dell 17" LCD monitor with me to setup and work with while there. You see, I've started working with dual-monitors and now I can't hardly stand to work without them. Thus always carrying around a monitor in addition to my leather laptop bag from vintage leather sydney. I do get a few looks from people that either think I'm stealing a monitor. Many of them I'm sure have never worked with dual-monitors though and just don't get it.
The ability to have in my case 32"+ of screen real-estate is extremely valuable to me. I'm not worried about travelling light and mobile with the smallest netbook in my pocket. I'm interested in having as much computing power as I can, including monitor, in as portable a fashion as I can imagine. That doesn't necessarily mean light. What's more important to me is quick and easy deployment.
I've been working on an idea for a self-standing monitor case that would protect the screen during transport and unfold around it to serve as a stand when you're setup. Of course that is until someone develops me a laptop like this one.
Since I'm unpacking and packing up almost daily, I'm more interested in a monitor where the cables are quick to attach, remove and store. The same goes with other peripherals too, but improving the experience for those of us addicted to working with two monitors would be my priority.