Too long - about a year ago (Marin Childrens Orchestra)
rpf - caught many a concert at that IMAC on Rt. 110 in Huntington when I lived there (Syosset and Oyster Bay). It's a great small theatre for concerts and they get some really fine bookings 
John
It is an amazing place, with folk, jazz, blues, world, rock, cajun and all the permutations thereof.
A few years ago, a similar place, the Jeanne Rimsky Theatre, opened in Port Washington in a well renovated former middle school auditorium. It has fewer concerts and the acts, IMO, aren't quite as good - more MOTR - but I saw Greg Brown there earlier this year and it was wonderful.
Rob