A handle (pseudonym) that was used on dial-up BBSs in the late-1980s until approx. the turn of the century. Used on internet BBSs (forums or even fora if you want to be anal about it!) even to this day {early-2013}.
Can also be used to describe a potato that tastes like piss.
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{John}: Martha, this fucking spud tastes like piss!!!
{Martha}: Sorry about that John, you must have gotten a urine potato!