Cheats:
 Go to the daggerfall dir on your Hard Drive, find a file called Z.cfg
 open it up and add the line: cheatmode 1
 Now start up the game, while in a dungeon hit ctrl and F4 to toggle
 'god mode'.
 Alt and F11 will put you bacl on the last thing you were standing on,
 if you fall into the 'void' and can't get out, (you may have to hit
 this key combo a few times)
 Ctrl F1 -activates all maps, not sure exactly what this one does or
 means.

Demoversion:
 Press [Alt][Q] while playing the Demo to bring up the cheat menu.
 You get options like

 1) become vampire; you get +20 on all statistics (up to a maximum of
    100 on any individual statistic).  Your extra normal spells are
    Acidic field, Telekinesis, Calm mortal, Charm Mortal.  You can
    also cast Levitate without expending any spell points
 2) become werething; +40 on strength, agility, endurance, speed, (up
    to a maximum of 100 on any individual statistic).  You can cast
    Lycanthropy without expending any spell points You do however
    lose some health.
    You can also change from being a vampire/werething back into your
    former state.
 3) go up a level
 4) get extra training in specific areas
 5) toggle dungeon
 6) toggle compass

 (The actions of 3-6 don't appear to work properly in the demo)

 7) find treasure

 From THE UNOFFICIAL DAGGERFALL FAQ, version 0.99 16 July 1996