Stellar sounds and the chance to win cold hard cash make it a December to remember. BUY London Sole Sale What: Scoop up adorable ballet flats on the cheap. Why: You’re a Sole (wo)man. When: Thru Dec. 14. Where: Online at londonsole.com. Enter code LS888. HEAR Elvis Perkins What: Folky excellence from a singer/songwriter whose debut album will be released next year. Why: Elvis has left the building. Where: Online at elvisperkins.net. DO Bring Back the Fizz: Battle of the Bands What: Cyndi Lauper judges contestants vying to remake Alka-Seltzer’s “plop, plop, fizz, fizz” jingle; winner receives $10,000. Why: Oh, what a relief to win. When: Enter by Dec. 22. Where: Online at plopplopfizzfizz.com. Holiday Party Excuse Generator What: You describe the undesirable soiree; it whips up a thanks-but-no-thanks letter. Why: You may be excused. Where: Online at holiday.enlighten.com. EAT Masala Chocolates What: Heavenly Belgium chocolates get a kick with ingredients like rose petals and basil-honey in shapes like owls and penguins. Why: Spice things up. Where: Online at masalachocolates.com.