Don't take my word for this, as I have not yet had the chance to personally test it out for myself, but what about the iPad? That is pretty cheap (500 dollars) and there's different apps on that which will basically function as a pretty huge and sweet remote control for Logic, including faders on the screen.
Just to clarify, I have tried an iPad and think it's great, but I haven't tried those particular Logic controller programs on it yet. As long as the latency is decent, then it seems to be a very nice option. The bonus of course is that you not only get an awesome Logic remote, but also get the benefit of all the other uses of the iPad, when you're not using it for Logic.
Motorized faders don't really impress me and most feel like complete, cheap crap, unless you're willing to buy the really expensive ones. I haven't yet tested the Euphonix ones that you're talking about.