Welcome philou,
yes it is possible.
One thing you need to do before you start is to create (and format) a
FAT32 partition as the
first primary partition on the drive.
At least 500 MB, up to 3 GB. Make sure the boot flag is set on this partition.
Then you would do the same steps as described to set up a usb stick/key/pendrive.
In short: burn the iso, boot it up, plug in the usb drive, start the "Create Live USB' wizard.
The system wil be a live system with dynamical hardware detection, portable.
For computers which can't boot from usb you would carry the Live cd and start it with: livecd fromusb and plugged in usb key.
More info here:
http://www.mcnlive.org/usblive.htm--chris