The invention provides, in some aspects, a power supply that includes a first rectifier circuit configured to receive a first AC input and to generate a first DC output, a second rectifier circuit configured to receive a second AC input and to generate a second DC output, and a storage unit (e.g., a capacitor) configured to store charge from both the first DC and the second DC outputs. The storage unit can itself be configured to supply that stored charge as DC power, e.g., to a computer or other coupled device.