Crystalline 'sponges' offer a way to impose order on small molecules so that their structures can be solved by X-ray crystallography. This enables nanogram quantities of material to be analysed using the technique. See Article p.461 X-ray single crystal diffraction provides direct structural information of molecules at the atomic level and is recognized as a reliable structure determination method. However, as its name implies, the technique has a limitation, the sample needs to be available as a single crystal, the growth of which can be a time consuming process of trial-and-error. This paper describes a new X-ray analysis protocol that does not require crystallization of the sample itself. Instead, crystalline 'sponges' known as metal organic frameworks are used to soak up a drop of a liquid guest containing the target molecule. The sponges contain pores that recognize the target molecules and bind them in an ordered array, enabling the crystallographic structure analysis of the absorbed guest along with the host framework. The method is demonstrated with the absolute structure determination of a scarce natural product, miyakosyne A, using little more than a trace, 5 μg of sample. Corrected 8 April 2013