Open-source light-sheet microscopes for imaging cleared tissue

Yup it is not a cheap area of microscopy - commercial SPIM systems typically range from $250K to around $1 million (though there are some significantly cheaper than this) and you can build them for significantly less.

I think the hope with both OpenSPIM and mesoSPIM initiatives is by getting design information out and plans out as open source, the community has a reference system they can experiment with and find mechanisms that work to help bring the price of the systems down. Typically, most expensive parts are things like cameras and detection objectives. If you can scrounge parts, find alternative units (cheaper cameras etc.) you can find means to significantly reduce cost. Similarly, if you are trying to push the boundaries - you can see where you can gain potential advantage by substituting sub-systems for greater resolution units etc.

My hope is that through community initiatives like OpenSPIM and MesoSPIM, the community can reduce costs of these systems by an order of magnitude over the coming years, while at the same time, using similar reference systems other leading teams can push the boundaries and highlight what is possible.