This depends on what you are thinking an HR person or group will do for your company. Is this the payroll department, keeping track of hours and salaries and vacation days and benefits? Is this the person/team responsible for hiring new team members, or at least dotting all the i's and crossing all the t's filing the necessary paperwork? Is this the person/team that handles disputes between staff members or handling discipline issues when somebody crosses a line? Knowing precisely what you need will direct you accordingly; just keep in mind that always, always, HR exists to protect the company from its employees.

An ordinary average guy

Clocks would be fine, Very small lamps (some LED Only?) and anything bigger than a novelty with a motor or tries to change a temperature will eat more amps than what USB ports deliver or cables are designed to carry. I encourage you to continue your research though; please review motor home or camper power use - in many cases it's 24V DC and may answer many of your questions for how and what. Or better yet, invent motors or heating elements that are actually practical and only require < 1 amp and 10V to run- that would make you a fortune! Cheers, Craig