The March 2007 issue of Cottage Living's version is rafia-over-cork, with a grid of grosgrain ribbon. They provide a handy PDF template of the number labels, which are attached on with velcro. We like it, but would worry about the nailhead tacks that hold the grosgrain up, not to mention the pushpins. But if your children are past their toddler years, this wouldn't be an issue.
Martha's chalk version, brought to our attention by Adrienne, is also a full wall treatment. The basecoat of the wall is black chalkboard paint, with four versions of grey used to block out the days. Numbers are just chalked in. We love the colours in this one, but if we were doing the Martha version, we would have done a basecoat of magnetic paint underneath the chalkboard paint, so that we could hang invitations and event notices up as well.
One idea, two executions. What do you think?