Everybody knows about the cheap solution mounting a glass plate with these metall paper clips. However these clips are dangerous because your head can crash into if you don't take care. I solved this problem easy by cutting off the thick end of the clip. It is a little bit more difficult to mount the clip after modification (i use a large screwdriver) but it works pretty well. And now, i don't care any more about crashing, because the thickness of my clips is less than 0.3 mm and fits under my head. Update: Make absolutely sure that the clip does not press too firmly together. This can may in the long run break the glass. Use a screwdriver and pliers to wide the clip a little bit so that the glass is fitted enough not to slip - but not more.