Expanding my carbon footprint

What is the carbon footprint of the global conference industry? It's probably about time we started thinking about it. I assume it must be horrendous, but I've been cycling to work religiously for the past 15 months, so hopefully that will go some way towards offsetting the damage I will do in flying to Berlin to appear once again during the pre-lunchtime comic relief spot at VON. Maybe it's time for the telecom conference industry to harness some of the productivity tools it has been touting for so long and go virtual?