The “Ultimate Lens Hood” seems like a good tool. It is still to be seen if it is stiff enough and/or a bit sticky so as to easily stay in place on the glass surface. It has the potential for being very useful but how easy it will be to handle with different lenses is still to be seen.
I just made my pledge for one ULH at Kickstarter. If you want to get your own, be aware that the campaign is about to end.
See my earlier post to learn how I have been managing until now with normal collapsible lens hoods made of rubber. I recently uploaded a gallery of photos from an ongoing project where I am taking photographs through train windows.