What's better than a big visable chart? A big visable moveable chart.
Once you've discovered the joy of whiteboards and adhesive banner paper and self stick easel paper, wall space quickly becomes a very limited asset. It's not uncommon for our walls to be covered with big visable charts. Actually it's not uncommon for some of our big visable charts to be covered with other big visable charts. (Hey, it's an easy way to find the agenda of last month's meeting. It's behind the agenda of this week's meeting.)
But sometimes it's nice to take the big example you sketched out on the whiteboard and put it right next to where you're working. Or maybe you want a big notice at the entrance to tell people that the repository is back up with a new hard drive. Or maybe you just need a whiteboard while you're working on this card and you're running out of walls to nail whiteboards to.
When that happens, it's really nice to have a rolling whiteboard. Ours are a great size, rolling easily through doorways, and narrow enough to go wherever we go without worry. And having them being a whiteboard all the way down is great. That bottom area gets used more than you might think.
Besides, sometimes the wall space is needed for something other than a big visable chart...