These coasters look particularly fantastic made from bamboo and other woods, as well as turning out very well on lighter colored felts
The engraving comes out subtler on acrylics, but looks pretty neat made with a tint against a light background.
You can also make these very cheaply on corrugated cardboard - though note that parts of the lettering will fall out.
As per the screenshot of the design, this file is set up to make four coasters on any one type of material - using Ponoko's smallest P1 sheet size.
Add this file to your Ponoko Personal Factory and add a material (P1 size) to get an instant price to make it, or download it and customize the design in Inkscape for the personal touch.
Example making + material costs on a free Personal Factory Account:
* on Amber Bamboo 2.7mm -> $15.79 USD + shipping & handling
* on Orange Felt 3mm -> $18.46 USD + shipping & handling
* on Light Blue TINT Acrylic 3mm -> $15.67 USD + shipping & handling
* on Corrugated Card - White 4mm -> $12.18 USD + shipping & handling