New
#20
What he said, the Micro SD card is essentially the Pi's hard drive. The current Pi only has 1 gig of RAM. click my "My Computer" link in my profile. You can set it up to run from RAM, the default setup doesn't do that though.
For me, being able to boot from my laptops SD card slot would mean I could when needed boot from Linux to do Pi stuff, without having to mess with dual boot etc.