We definitely live in the days of rechargable technology.  I'm not really that old, and I remember when most gadgets took AAA or AA batteries... and getting rechargables included with the device was always an (expensive) upgrade.

Nowadays, though, pretty much every gadget or portable electronic device has rechargable batteries included... MP3 players, PDA's, phones, laptops, even toys.

With the convenience of rechargable batteries does come some problems, however.  Many devices use the Lithium Ion standard type battery, which has many advantages... but in some cases, a limited lifespan as well