I took a drop of water from the fountain in front of the Green Library and observed it under the foldscope with dark filed. The dark filed image was by adding another lens between the light and the sample. Surprisingly I found this golden creature which may be a unicellular organism due to its size.

The scale bar was estimated via an image of the 5 μm nylon filter (in the foldscape toolkit) as shown below. I averaged over 10 holes to get the length.