• Ultra-low-cost microfluidics: Sharpie ink on glass slides creates surface-tension-confined “virtual” channels (470–3000 µm wide) that can be erased with acetone and redrawn, demonstrated live with algae-laden water to steer flow and generate vortices without CFD modeling.

• Disposable “fingernail immunoassay” proposed: antibody spots embedded in nail polish that change color within 3–15 min to detect HIV or other pathogens, framed as a “teen novelty” product to sidestep FDA home-diagnostics rules.

• Rapid prototyping materials compared: consumer UV-curable resins (Magic-Glos, nail polish, fiberglass resin) vs. lab-grade thiolene and Kodak PCB masking compounds; bulk acrylic/polyester resins in gallon cans identified as cheapest route.

• Reconfigurable microfluidic circuits: concept of magnetically steerable Sharpie-ink-coated beads sandwiched between glass slides, allowing external magnets to redraw channels on demand; additional ideas include spinning CDs as disposable substrates and actuators.

• Fluidic logic and robotics: speculation on fully fluidic robots built from photopolymer techniques that home in on engine noises to siphon gasoline or offer windshield-cleaning services; electrorheological (cornstarch/silicone-oil) micro-valves for robotic fingers discussed.

• Key resources shared: Cornell KMODDL mechanism library, open-access papers on inkjet-printed microchannels and PVC/cellulose acetate patterning, BioBarCamp recordings on portable PCR and colorimetric disease detection, droplet-microfluidics review, Dean-vortex micromixer, and genetic-algorithm-based automated microfluidic design papers.

• Open-source FEM tool Elmer (elmerfem_5.4.2-6~2lenny_i386.deb) installed and GUI launched, though mesh-generation crashes and sparse tutorials noted.

• DIY biology mishap: Carolina E. coli and fluorescent-protein kits left unrefrigerated for three days, prompting discussion on salvageability.