PocketMatrix

The one you can afford?

AFAICR, the CF card does NOT have an extra battery in it (which is why it's "cheap").

The PCMCIA and dual PCMCIA jackets do - I have the latter, and my battery life is very good (the single has one extra battery and the dual has two extras).

Also, make sure you take all of the power-saving precautions like turning off the backlight/screen when you're not using it.

Cheers,

Refractor

Is it possible to get a version of this for my em500. Also, is it possible to use normal alkaline batteries to charge it up?

You can also try to build a battery extender, Adrian's Rojak Pot has a very good .

I think I should give it a try, too.

Ive seen at some stores some power cartridges that plug in to the bottom of Jornadas, Casios, and Ipaq's. I think they said it lasted around 4 hours, im not sure. You have to buy cartridges when the old ones run out and they are pretty expensive for short term use ($10)