Thanks. I meant both those things. The ctrl-g thing is what I have been doing, I was just wondering what others are doing.
As far as linking etc, in 3DS you have a shape called nullObject which is basically just a crosshairs. What I have been doing in Maya is what you suggest and just use whatever geometry and make it non-renderable. I was just wondering if there is a better way of doing it. But now that I look I see there is something called Empty Group that does exactly what I am looking for. Silly me. Thanks!