A Japanese artist who goes by the name Sputniko! (punctuation included) has designed and built a machine that simulates the experience of menstruation, for use by those who don't spend a week dripping blood and uterine lining out of their genitals by dint of biology. The device includes electrodes to induce abdominal cramps, and, from the looks of this video, some kind of slowly released red fluid.
"Takashi builds the Menstruation Machine and wears it out on the town with a girlfriend, strutting around a shopping mall and occasionally doubling over in pain. Thus an internal, private process is transformed into a wearable display of identity," explains Sputniko! "Since the 1960s, advances in hormone-based contraception have, by suppressing ovulation, made monthly periods no longer biologically necessary. Sputniko! notes that the Menstruation Machine may be particularly desirable in a future in which menstruation in fact becomes obsolete." The video and the machine are on display at the Museum of Modern Art now.