Maria designs necklaces that she then cuts on the laser. She uses an industrial wool felt. The smell as they outgas is a bit like burned hair. Her blog’s got information about her jewelry and other creative projects.
Laser cutting felt is a great way to create complex shapes in felt, which can then be sewn or glued together with traditional crafting techniques. Natural fiber felt will have a burned edge, and will smell like burnt hair. Polyester fiber felt will have a fused edge, and a burnt plastic smell.
There are photos of this project technique.