Have used the same position as bmwcoolk1200 in the past, trouble is switching the camera on/off unless you are stopped.. but thats not a biggy.
Some more samples...
Here's a quick trip from behind the screen, which is where I mainly use it as a crash-cam... (GoPro2 - 720P) with some added vignetting post-ride
And a much older clip with a panasonic handycam that was strapped to the right tip-over bar (very poor quality transfer) but it shows the wheel movement in relation to the bike frame and road. click
Having it way to the rear of the bike, in this case on a trailer
What I'd like to do next, when I get some time... is have it a bit like a MotoGP cam behind the rider on a gymble, but up high above & behind the passengers head so you get a sense of the lean, plus all the direct view we see when riding. One day I'll get a round-tuit.
Not legal to attach cams to helmets over here (big stink about that at the moment) and while that gives a lot of options, the constant head-movement can give the viewer a bit of vertigo / car-sick type feeling... I know I suffer from it badly and can't watch the. I need a stable reference point all the time.
And just for a bit of fun, 2 bikes, 2 camera positions, a great twisty road and a little bit of editing click
have fun, whatever you do!