I must have been hiding under a rock because I was talking with a mate how we'd probably be able to get the IOS7 look already and he mentioned parallax LWPs and I just shrugged.
There is something about them that I just love.
The one i've ended up buying allows for any image to have the effect applied to it.
This one is planets and stars etc and is also very effective.
In any case, hopefully someone else sees this and likes them.
I believe using a custom rom or maybe widget locker you'd be able to make this work on the lock screen, too...