Another anti-spindown utility Mac OSX Software Development, Leopard, Tiger, Pennsylvania, Lehigh Valley, Bethlehem, Allentown, Easton, Pa
$10 shareware app that keeps those pesky external drives from spinning down.
Simply add the volumes you wish to no longer spin down, then enter in an "interval" (for instance... if your drives are set to spin down after 60 seconds of inactivity, enter in an interval of 59). The lower your "interval" number, the less chance there is of your drivespinning down.
[From Mac OSX Software Development, Leopard, Tiger, Pennsylvania, Lehigh Valley, Bethlehem, Allentown, Easton, Pa]
Of course, there is the freeware disksomnia which we mentioned a couple of months back from Digital-Heaven