1. A structure comprising:an expandable structural frame adapted to expand to an expanded condition and retract to a retracted condition, wherein the expandable structural frame comprises a first frame member and a second frame member, said first and second frame members telescopically connected to one another for expansion and retraction of the structure;
a first electrical flow path adapted for providing electrical power to the structure in the expanded condition;
a second electrical flow path adapted for providing electrical power to the structure in the retracted condition, said second electrical flow path different from the first electrical flow path;
an electrically conductive switching device, said electrically conductive switching device comprising a caster carriage dongle, in a fixed position with respect to the first frame member and adapted to maintain moving contact with the second frame member during expansion and retraction of the structure; and
an expandable HVAC system including primary ductwork, secondary ductwork, and tertiary ductwork, wherein the primary ductwork, secondary ductwork, and tertiary ductwork are adapted to together define an expanded configuration and a retracted configuration;
wherein the expandable HVAC system defines a first fluid pathway in the expanded configuration and a second fluid pathway in the retracted conditions, said second fluid pathway being different from the first fluid pathway.