Modular conduit systems in which a plurality of tubular link components are interconnected to form a continuous conduit. Each adjacent pair of tubular link components has a ball-and-socket joint that enables the pair of tubular link components to be pivoted with respect to each other. The ball-and-socket joint consists of a ball attached to a first one of the pair of adjacent tubular link components and a socket attached to a second one of the pair of adjacent tubular link components, where the ball is positioned within the socket. The amount of friction between the ball and the socket is adjustable, so that the amount of force required to pivot the pair of tubular link components with respect to each other, which is dependent upon the amount of friction between the ball and the socket, is variable.