First Appearance: The Beginning (November 7, 1998)
"Pandora" is Nick's personal computer, so named because (and we quote) "open the box and bad things happen." In the earliest of strips Pandora has a tall tower case and large CRT monitor, often sporting an organic chemistry stick-and-ball model set configured in some random molecular configuration. (Nick, after all, originally majored in chemistry.) Nick was also known to stick Post-It Notes copiously on the sides of the monitor, at least until he acquired his PDA to perform similar tasks.
Of course, Pandora has featured much less frequently over the years, so it is unknown whether she is still Nick's current PC. Given that Pandora first appeared in 1998, that's extremely unlikely. What is unknown is whether or not Nick had given new (supposedly) mythological names to replacement machines, or whether each subsequent machine has carried the mantle over time ("Pandora Mark IV").