A Holographic Microscope for Just $250

The paper on arxiv: http://arxiv.org/abs/1211.0336

The reduction in size is possible because they found a way to not use a beam splitter and lenses. Comparing the diagram on Wikipedia makes it easy to see how that could save a lot of space: http://en.wikipedia.org/wiki/Digital_holographic_microscopy

It would have been nice to see either a model or conventional images of their test targets for qualitative comparison to their resulting holograms. Still cool stuff though.