SD card with OS systems?

I read on Wikipedia that there are MBs that can boot up from SD (SDSH) cards instead of using Hard Drives.
I am curious, any one has done so or knows which ones that are capable of doing that? Booting up from an SD card opens the possibility of changing to a different OS or system by just replacing the SD card, a neat way to do so!
Comments anyone?

Chromium OS would fit on a SD card and so would several versions of linux. Just get a USB card reader and set your bios to boot from USB and it would work.

massahwahl said:

Chromium OS would fit on a SD card and so would several versions of linux. Just get a USB card reader and set your bios to boot from USB and it would work.

Click to expand...

Yeah, you could do that or just boot straight from USB, cheaper and better, imo...

I've installed Ubuntu on a USB hard drive before. It's slow as molasses because the transfer speed isn't fast enough. It was functional, but you wouldn't want to do much more than surf the internet.