Although diving under the covers or firing up a chainsaw may save you from lesser ghouls, it will never get you in shape in time to face the bogeyman. Prepare for scary smackdowns with today's Groupon: for $35, you get five SPX Pilates or spin classes (up to a $110 value) at Pilates Platinum's Hollywood, Brentwood, Venice Beach, or Santa Monica locations.

SPX Pilates's 55-minute classes increase the intensity of standard Pilates with Sebastien Lagree's Proformer machines, ultimately strengthening, toning, and tightening jelly-like muscles in less time. Spinning classes take place on Star Trac Spinner NXT bikes, which can be customized to fit any stationary cyclist. The small group sizes and the team of motivating exercise experts help keep participants excited as they slash and burn excess body mass. Confused newcomers and answer enthusiasts can consult the site's comprehensive FAQ for help before the first class.