extension cords for mouse and keyboard

[pan@ATHENA.PANGARO.dialnet.symbolics.com (Paul Pangaro)]

In moving my console a bit further away from my head (trying to stay
under the 1 milligauss exposure level currently being recommended by
MacWorld, for example) I have added an extender arm under my desk that
holds the keyboard and a small pad for the mouse. This is nice, and can
be swung out of the way under the desk when not in use (maybe for the 5
minutes a year when this is true...) But the real desire is to get the
cords for keyboard and mouse to run under the desk and away from the
surface of the desk --- cosmetic and practical too. I need another 2
feet or so.

Has anybody done this? Any sources for these things that you can
suggest. Thanks.