a modular stackable hub system that includes at least one stackable hub for communicating any combination of a multiplicity of electrical signals , for example , isdn modems , port replication , usb to ethernet , ethernet switching , direct current , alternating current , routers , kvm switches , cable modem , firewire , dvd drives , cdrw drives , and usb . the stackable hub would include at least one upstream port and at least one downstream port for releasable mounting to other components in the stackable component system , and may include at least one external port and / or at least one bay for receiving a removable module . the upstream port would communicate upstream electrical signals , which may be any combination of the electrical signals , for example , the aforementioned electrical signals , with an upstream component , and may pass these electrical signals on to the downstream port , where a separate downstream component may be connected , and / or the external port . the removable module may , for example , be a surge protector . consequently , any number of stackable hubs may be stacked together and releasably mounted to and communicating electrical signals with a base unit .