In no particular order:
Nervous System. Beautiful, sophisticated takes on structures from science and nature, in a variety of materials.
Dimonus. Gorgeous and unique enamel and gem jewelry. Many of their designs are based on plant cells.
Norsola. Funky metal designs based on biology and astronomy themes, among others.
Giroofasaurus Vexed. Ceramic jewelry with biological motifs including viruses, mitosis, nudibranchs and many others.
Elinart: Amazing embroidered jewelry and accessories featuring lichens and mold.
Noadi. Mostly polymer clay and resin pieces, many with microbiology and marine biology themes.
Super Photon Factory. Laser cut wood jewelry including viruses, flasks and more.
NBDesigns. Precious Metal Clay jewelry in biological motifs ranging from the safe (flasks, DNA) to the adventurous (chick embryos)
Nicholas and Felice. Silver jewelry stamped with geeky symbols from math and physics.
SurlyRamics. Surly Amy is the queen of skeptic and general science themed ceramics.
Mars Bling. An accessory line made with images sourced from NASA missions.