Pretty easy, just a power supply for an IDE to USB adapter 14 bucks on ebay, a 80mm computer fan I had lying around, a round or square metal plate. You glue the plate to the fan slightly offset and you enclose it in a wooden cigar box. All told, less than 20 bucks. Shakes your e-liquid during steeping to speed up the process without you having to zip tie them to a reciprocating saw. Haha. May take a bit longer but it's quiet and passive and you can leave it in your garage.
