Anne Loucks made a little cardboard placque with a downward extension, put it over her keyboard, and by charmign her cat into walking over it, the placque pressed down on the space bar, agreeing to Adobe Reader's EULA. Her cat might not be a legal entity, but the fact of the matter is that she herself did not agree to the EULA, so technically, she shouldn't be covered by it. Right?
Back when I conducted my little investigation into the legality of EULAs in The Netherlands, several legal experts concluded that clicking "I agree" is a valid means to acknowledge an EULA. However, I did not ask whether or not this would extend towards other members of the household, who might also be using the covered software. For instance, Apple's EULA for Leopard consistently speaks in singular, therefore limiting the EULA to the person who agrees to it. It also says "by using you agree" but that won't hold up in court in this case, since someone wandering into my apartment and using my computer will not be presented with said EULA, nor will he know what software he's using.
Still, the point made is an interesting one, and it might very well be possible that you could convince a judge this way. My two cats, Twiek and Alice, are standing by.