I thought the Pocket Coin-op would look nicer with some tapered edges. the rounding also makes the opener lighter and speeds up the print a little.The thickness, coin-size, and taper are all adjustable in the scad. I didn't bother to test changing the other variables as I'm pretty happy with that geometry.Bonus: Are you full of jealousy seeing all these dualstrusion parts popping up everywhere? well now you can stick it to the man with a three color bottle opener!For 1 color just choose taperedopener.stl or taperedopener-M.stl and print.For 3 color (you'll need a Thingomatic for this):Print taperedopener.stl. Make note of the number of layers and the Z-Layer thickness.In ReplicatorG, open the motherboard settings form and write down the zoffset value.Now change the zoffset by the number of zlayers and layer thickness (newZ = oldZ - nlayers*layerthickness)Print taperedopener-color2.stl in a different color. When skeining uncheck "Activate Outline".Print taperedopener-color3.stl in a third color. When skeining uncheck "Activate Outline".Open the motherboard settings and return the zoffset to its original value A note about Coin Insertion: It had not occurred to me that people might try to insert the coin by pausing mid-print. Apparently this works, but it's not what I do. After printing I slide the penny into the slot as far as I can. Then using a pair of pliers (one jaw on the penny, the other on the short edge of the opener,) I squeeze the penny in the rest of the way.