As it so happens, it IS possible to fart out of a man's genitalia, though it is not a true fart. During a brief stint in the hospital, a colleague had a catheter inserted in his urethra. Upon its removal (which was apparently excruciating, go figure) a sizable amount of gas was trapped inside the tube, due to the distension of the tissue. Upon his next urination, it was all forcefully expelled, creating a farting sound. He says that this occurred at least 3 times, within 24 hours of the removal of the catheter, though each successive "fart" shrunk progressively.