Made for the “last meter” contest. Although all parts together can be printed for less than 4m filament (not tested with the uploaded gcode, since I have no Prusa printer yet, but a comparable setup was used on my printer successfully, see image), you can/should print each piece separately with your favourite settings instead! This way you can utilize your last meters more easily, since each piece needs less than 2m of filament, even with fat/robust settings. 

Assembly guide: print a pair that suits your laptop best (I added versions with 11mm, 14mm and 17mm height, if you need a smaller or bigger version, scale to your liking), and screw them onto your board (board thickness should be bigger than 12mm). Pre-drill a small hole where you want to mount the holders, this way you will get the screws easier into the board. The holders are slanted on one side, just test which one fits better on the left/right side (I use the slanted parts on the outer ends).