Your back muscles whine with every twitch, your hair is an affront to good taste, and your nails look like a deck hand's. But the effort required to go to the nearest spa is simply more than you can muster. Spa to Go Essentials will come to your home, office, suite, boat, or cabana ready to rub, style, and file you back into form. Claudia, a Spa to Go masseuse, asks for your preferred pressure level and focal points before easing into a $70, hourlong Swedish massage. At $20 a manicure and $40 a pedicure, the nail services are a bit pricey but precise. A manicurist preps your hands with a lavish coat of lotion, then dabs warm cream on your cuticles and nips them clean. She colors in the lines, spreading polish to each nail's edge without straying into fleshy territory. Finally, co-owner Christine Lieberman, who opened the Worth Avenue version of her Nantucket spa in December, will send you out to that soiree with a $30 blow-out or $50 up-do that makes the morning's frazzled locks seem a distant apparition.