You should start reading EULAs sometime; it can be pretty fun, and there are often clauses that you might find surprising. For example, unless I'm grossly misremembering, there should be something interesting in the Oblivion EULA about mods and their ownership.
I still have a fond memory of Freespace 2 and its "You may make copies of the Software for your personal noncommercial use and to give to friends and acquaintances on a no cost noncommercial basis" clause (in the in-game EULA). Don't worry, most EULAs don't give you this freedom.
