Yes, and ofcourse Nope.
Ahem, Yes you can put any Apple OSX you own on any Mac requirement met compatible computer, however some will surely say to tell your Friend to acquire their own legal copy for their own computers. Now that we've covered that obstacle, go Google the how to make a Dvd install disc from your Lion OSX download and partition a Hdd to clean install it on and your done, I'm told Lion installs a backup system file like Win 7, haven't used it, couldn't tell you yea or nea, but I haven't had any issues with a Usb or Dvd install, cheers my friend.