Is it serendipity or the miracles of Friendster that just as the hags of winter wheeze their frosty sorrows, several of my lifer-single friends have met a special someone? Let Cupid's annual visit mock us not, now that we have someone to help us warm the bed and brave the cold. So the question arises: How to celebrate this rare defrosting? (Aside from participating in vigorous gymnastics with our newfound partners!) One hearty recommendation: La Caverna, the Lower East Side's romantic, fun, and funky cave bar. Like a portal into a Flintstones happy-hour hideaway, the humongous room is a man-made cave complete with stalactites and waterfalls. Three Italian artists spent over a year creating the detailed rock formations before the bar opened two months ago. Wooful ambient lights warm and twinkle the many make-out nooks and crannies framed by wooden tables and large leather couches. The drinks are strong and well made by a friendly and accommodating staff. The dee-lish house special is the Caverna Cosmo: a fruity, semi-sweet cosmopolitan with splashes of mandarin and vanilla ($10). If you're into aperitifs, the Negroni is quite kicking with its Fernet and Campari double punch ($10). With regular DJs spinning and plenty of room to dance, the vibe shifts nightly. A midweek visit is suggested for the lovey-doveysit's usually less crowded. The overall effect is exotic, slightly over-the-top in a Vegas kind of way, and unlike anything you've ever seen on the Lower East Side.