Ask any adult if they know any electronic games, and the chances are they will claim they do not. Mention "Tetras" the original slot-the-brick game that came free with a million computers and the confessions begin.

"Ah well, yeah, Tetras . . . very good for keeping the kids quiet," is the usual response.

If one game of Tetras transforms your children, you may be interested to hear of the Christmas special, the Pop In One.

This is not one Tetras (or Tetrus-clone game) but 118. Hand-held and portable, it offers the user the chance to have the bricks flying from various directions at a wide variety of speeds and at 15 different levels of difficulty.

Parents planning a long journey may be wary of purchasing such a game, enticed by its calming effect on the child who is using it, but repelled by its ability to provoke fights over whose turn it is. At £10 a go, however, it might be worth buying more than one.

Available from Executek in the Grafton Arcade, Dublin, and other gizmo stockists.