I've seen a couple of web agencies using the term "War room" to describe a place where they sit and and brainstorm web projects. The room usually contains a lot of sketches on the walls and it all looks very impressive... What are the components for an effective war room environment?
If the war room is for making a tight deadline, then I'd say the comment from @Roger-Attrill is perfect. Especially the coffee. Don't forget the coffee.
However, if it's used for brainstorm sessions, there might be some other components you can use for an effective and most of all creative brainstorm session. Make sure people inside the room don't get easily distracted. Provide some of the basic needs in order to keep them focussed:
Might not be exactly the information you're seeking, but I sure hope my contribution will somehow help :) Also, if you need information on how to organize a brainstorm session, Wikipedia offers some kick-start information on the basic techniques: http://en.wikipedia.org/wiki/Brainstorming
And seriously, don't forget the coffee.
In describing a place where "where they sit and and brainstorm" the term think tank is perhaps more appropriate. The term war room originated as a term to describe the command and control center to wage a real war. The English war rooms that Churchill used in World War II are an example.
A key characteristic of any war room is the need to keep all participants constantly updated on rapidly changing situations. The emphasis is on effective display of real-time data. If you watch an old war movie you will see lots of people moving pins in maps or using grease pencils to show where the ships and planes are. Today a war room will have lots of phone lines, laptops, tablets, flat screen displays on the walls etc.
Today war rooms are typically used for a crisis of a limited duration, such as a natural or man-made disaster. Since when and the nature of such use is unpredictable, the room should be as flexible as possible. Think of a hurricane of a nuclear plant explosion. A perhaps less dramatic use for a company might be when the CEO is in a plane crash or the data-center with your web server was just destroyed.
Since people are often called in unexpectedly, and need to remain for an indeterminate amount of time, it is essential to provide them with everything required such as food, supplies etc so that they can operate at peak performance. Often sleeping and bathing facilities will be provided as well.
A think tank is similar to a war room but without the sense of urgency. People can work regular hours and go home at the end of the day. The is no external event driving the time line. What is in common is the requirement to effectively visualize and share ideas and information. Any tools from sketchpads or even backs of napkins all the way up to full blown 3D animations is appropriate.
To get the maximum benefit out of a think tank session provisions should be made to record and document the session. Use of both a facilitator and a scribe along with video cameras may be highly appropriate provided it does not inhibit information sharing (some things people don't want to say on camera).
The one constant reason for either brainstorm or war room being successful or not has always been the facilitator, in my experience at least.
This is the hardest job, this person needs to be able to sense where the discussion and keep everyone on task, keep the momentum going and also have a really good feel for when to let people go off on tangents and when a "direction-injection" is needed.
The best experience I had was with a creative director who was way good about everyone having a lot of fun and being crazy and harnessing that to get out the good ideas. He was also a high-level "Why?" person who helped us think about the overall vision instead of only tactical approaches.
And the one thing he has consistently done better than anyone else is set direction and tell everyone (even half-way in to the ideation process) where we need to go. After sometime he would always narrow down our approach based on what we had come up with, he took what he thought had most potential and told us we would go down that path. We would then start working on that and then he would set more direction.
This way we had much freedom and fun but the direction was clear and everyone was happier for it. Not getting stuck and still giving the process the time it needs.