The second law of thermodynamics and the first law of Nelly lyrics hold that ambient heat and clothing have an inverse relationship. Disturb the natural order with today's Groupon: for $15, you get $30 worth of yoga apparel online from wild buddha designs. Designer Gerri Feldman, a lifelong yoga devotee, makes her own line of extra-soft T-shirts, wraps, thermals, and hoodies inscribed with messages of joy, compassion, and open-heartedness. Salute the sun clad in the vintage feel of a burnout-fabric Ganesh T-shirt ($30), or make a metamorphosis wearing the Transformation in Progress tank ($24). This Groupon is valid toward sale items.