Casio DC-E700 ============= A accidentally found such thing: an old databank which is somewhat special: * is has size of a credit card, * it is almost as thick as a credit card (~1.5mm), * it runs on solar cells ONLY (no battery), * it uses an EEPROM to store data (~300 items). Well, things are not so simple - it needs electricity to be change the EEPROM data. So there is a dock which incorporates a CR2015 battery and which is slightly bigger that a credit card is. And the keys are far from comfortable. The solar cells energy is need just for searching and reading of data. It's a cool gadget, though.