In keeping with the infamously goofball Cobb County, Georgia, disclaimer stickers to be put on science books that mention (gasp) evolution, here's a collection of several more stickers that you can print out and put on books as well. For example:

Speaking as a Christian this is incredibly stupid. The stickers throw down the gauntlet and says prove it (and sadly also gives an opportunity for Christianity to be falsified). The evidence is overwhelming and has been the occasion of many to lose their faith. This is unnecessary because the idea of a young earth is a recent development in Christian theology. Note the following from Shedd in the late 19th Century.

Between the single comprehensive act of the creation of the angels and of chaotic matter mentioned in Gen. 1:1 and the series of divine acts in the six days described in Gen. 1:3–31, an interval of time elapsed. This is the old patristic interpretation. The very common assertion that the church has altered its exegesis, under the compulsion of modern geology, is one of the errors of ignorance. The doctrine of an immense time prior to the six creative days was a common view among the fathers and Schoolmen.

...

Respecting the length of the six creative days, speaking generally, for there was some difference of views, the patristic and medieval exegesis makes them to be long periods, not days of twenty-four hours. The latter interpretation has prevailed only in the modern church. [emphasis mine]

Who writes this stuff? Arthur Dent?