HANOI (Reuters) - Asia's craze for Japanese virtual pets, known as Tamagotchi, has taken a new twist in Vietnam where schoolchildren are ditching high technology and high costs in favour of the real thing. A Ho Chi Minh City newspaper reported booming sales to children of tiny newly hatched birds, which it said were disrupting classes in the southern city. Just like the hand-held Japanese computer game, the pet grows and tweets when it needs attention or food -- and dies if neglected. Novel concept. The tiny birds cost around 25 cents each. The local price of the electronic alternative is around $30.