Abstract: A modular support system is provided herein. It includes one, but preferably at least two, elongated bars, each having a longitudinally extending slot traversing substantially the entire length thereof except at the ends thereof. A clamping member is provided for engagement with the elongated bar and preferably for use when at least two elongated bars are used, for clamping two such elongated bars together at any desired angle, e.g. at 180.degree. to each other. The clamping member comprises a pair of complementary, essentially U-shaped members, with the space between the arms of the "U" being substantially the same as the width of the elongated bar, a central longitudinal ridge between the arms of the "U", adapted to enter the slot in the elongated bar, and preferably also a pair of pins mounted, preferably removably, on at least one ridge and adapted to enter cooperating aperture e.g. in the flat base of the "U", and means for providing secure, e.g.