"Come play with us!" beckons HiChristina, the whimsical performance-art duo of Fritz Donnelly and Christina Ewald. And indeed, going to a HiChristina gathering, where "the audience is the performance," is not unlike stepping into a child's idea of a party. Take, for instance, their recent event "Bikini Melt With Real Cheddar," in which they invited everyone to wear their bathing suits, make up crazy dance moves, and eat grilled-cheese sandwiches. Or how about the "Bike Wash Body Wash," which offered people the opportunity to be hosed down with their bikes? Donnelly and Ewald opened their performance space in Williamsburg in early 2009, moved at the beginning of this year to the Lower East Side, and are now looking for a new home. But in the meantime, you can check their website for upcoming events held at Dixon Place and other venues. Whether it's sing-along yoga or nude body painting, HiChristina is serious about only one thing: fun.