Not more than two physical forces in nature

The October 2008 issue of Physics Today had an awesome article, in which physicist Lawrence Krauss discussed a hoax article that he submitted to Physical Review Letters claiming that he had found a new, overlooked force of nature. In contrast to what we typically see nowadays, the editors of PRL showed that they had a sense of humor and fired right back, responding with several fake referee reports (one for each force of nature). Both the hoax article and the referee reports were reprinted in Physics Today.

Here is the abstract for the Physics Today article:

When I was a young assistant professor at Yale University in 1986, a great deal of interest was aroused by a paper that had appeared in Physical Review Letters (E. Fischbach et al., Phys. Rev. Lett. 56, 3, 1986). The paper argued that a reanalysis of data from the famous Eötvös experiment provided evidence for a force that violated the equivalence principle—the equivalence between inertial and gravitational mass. While many people were skeptical of that result, I reacted with surprise to the notion that the paper had survived the refereeing process, which at the time had very strict self-imposed requirements of general interest, importance, and validity.

I loved the following line from the Editor's response (that contained the referee reports): "Although all advise publication (after some revision) the Editors, in their usual arbitrary and capricious manner, do not come to this conclusion."

I approve!