Technologies that can warn mankind of impending calamity are truly vital, like offshore buoys that can predict a tsunami, or limos when they're being driven at high speeds by John Cusack. Forewarned is forearmed against the greatest calamity of them all -- PMS -- thanks to Flojuggler.
From a ballsy SF-based web developer named Selino, Flojuggler's a hilarious but real beta site that allows you to track and prepare for the "flo" of any number of women in your life with a super simple interface and alert system, the appearance of which is made all the better with ample red text and stock photos of happy, multi-ethnic people having a grand old time (so, expect a call from Benetton's lawyers). For each lucky lady, plug in the # of days in her cycle, # of days of flo, and the start date of her last period, and a handy table will display a forecast for each, e.g., "Joanna has 4 days left on her flo" (in red), or "Sonie has 1 day to her next flo" (in yellow), which you already know, because she's yelling at you and you're just checking your email. To set up alerts, simply drag as many gals as you want into a drop box below your table; then, two days before one of said gals hits the red zone, you'll get an email from Flojuggler that'll help you plan to leave town for your great Aunt's funeral. Again
Because Selino cares, little red boxes with random tips on how to deal with flo'll pop up next to your dashboard, e.g., "For all you boyfriends and husbands out there... a tummy rub during her period goes a long way", but not as far as Cusack, especially now that he's traded that limo for a plane!