Which distros install from USB/Live USB?
 

A friend of mine is working at a company that's getting a lot of netbooks. None of them have optical drives so USB is important. They are going to switch most of the netbooks from Windows XP to Linux.
I told him that both Ubuntu and Ubuntu Netbook Remix can be used this way. He installed both to a USB Drive and what he likes is at bootup it gives the option to either run it from USB as a Live Distribution or to install it to the hard drive. The installation would give him a way of switching them to Linux and in other cases for users who prefer Windows XP they still have the option of using a USB Flash Drive when they want to use Linux.
The question: What other distributions work this way? I have looked at Fedora, CentOS, Mandriva, and OpenSUSE. Would either of these install from USB or even work as a Live Distribution from USB or even do both? Are there other distributions that would do this?

Yep, alot of them do.

You can try Unetbootin to put various distro's on usb,
( http://unetbootin.sourceforge.net/ )

just remember to set all the settings on the gui and also, sometimes unetbootin
gives a weird boot asking for a password and the menu doesn't work.

It's also pretty easy to put any distro on usb, even multiple distro's on usb.