Think of Minor Demons’ PortaPets, distributed by Eruptor (310/305-9966, www.eruptor.com ), as virtual pets that have developed bad habits and antisocial tendencies. These creatures, which inhabit your Palm OS, are ill-behaved monkeys, homicidal kitties, radioactive fish, and other critters unfit to appear in polite society. If you don’t take care of your PortaPets (which cost $5; PortaMonkey is available for free), watch out. They don’t simply wither away–they become prone to Ebola infections and bouts of clinical depression. The faint of heart may want to stick to caring for real pets instead of adopting virtual ones; they induce much less stress.