Want to make a low-cost laminar flow chamber, perhaps for some light microscopy work? Check out the snappily named Fast Benchtop Fabrication of Laminar Flow Chambers for Advanced Microscopy Techniques by David S. Courson and Ronald S. Rock of the University of Chicago.
They describe a straightforward method for handbuilding a chemically inert, reusable laminar flow chamber in about an hour. I'm not currently in a position to need a laminar flow chamber, but this is a nice set of directions for anyone who might want to do some microfluidics work without having to go to a machine shop for expensive, custom-made flow assemblies.