I have the 1GB Microdrive in my CF sleeve. I notice a bit of power drain, but it's not to bad unless your playing mp3's off of it continuosly or something. I can't wait til' an MP3 player integrates Microdrive support like PocketTV does.<br><br>PocketTV has a feature that improves battery life. Instead of constantly reading off of the microdrive PocketTV reads ahead for around a minute and idles the microdrive, than a minute later it will read ahead again. This is very good and should be implemented into more apps.<br><br>If your concerned about battery life than Solid State memory would be the way to go. Solid state refers to drives with no moving parts, hense the term solid state

. these cards are normal flash cards but become very expensive if you want more than 128. I believe that the highest available solid state CF card is 512mb, however, I may be wrong. If you get the pc card sleeve and the CF->PCMCIA adapter for the microdrive than you won't notice any powerdrain because the PC sleeve has a built in battery.<br><br>hope that helps.<br><br>