On Tue, 18 Dec 2007 09:09:17 -0800 (PST), with neither quill nor
qualm, Miki quickly quoth:

Maybe this is too far off-topic... but one day I was thinking how nice
it would be to put hydraulic motors onto two wheels of a trailer with
an appropriate power unit. That way you could maneuver the trailer
around without the tow vehicle, to park it in a tight spot maybe.
With two motors and the little wheelie thing on the A-frame you could
skid-steer it.

Someone in the construction world has an add-on for wheeled
scaffolding moves. www.crawlerproducts.com Shorten one for trailer
use and use the trailer battery (if so equipped) to power it.
Good luck finding a price on one.

--
Seen on a bumper sticker: ARM THE HOMELESS