Customized version of http://www.thingiverse.com/thing:323616
Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=323616
Using the following options:
card_spacing = 10
gutter_height = 5
box_height_addition = 15
$fn = 20
card_spacing_ends = 2.5
cube_r = 5
gutter_width = 5
number_of_cards = 20