High complexity arrays of DNA probes have been used extensively in genetics research to help understand gene expression and the regulation thereof, but microarrays of RNA and other natural or modified nucleic acids can be used to quantify binding interactions beyond hybridization. RNA binding proteins, for example, play major roles in the post-transcriptional regulation of gene expression. Evaluating the specificity landscape of RNA binding molecules is necessary to understand gene regulatory networks and to engineer molecules that can be used therapeutically to modify gene expression. I will describe how we us ideas drawn from physics, chemistry and biology to synthesize new types of microarrays. The new RNA microarrays, DNA-RNA chimeric microarrays and 2'-fluoro-ANA microarrays, and others, can be used to study how proteins and other relevant molecules recognize and bind to specific nucleic acid sequences or structures.