Academic drug discovery laboratories tend to accumulate collections of compounds with great potential value that merely reside in fridges and freezers. Cross screening these libraries against alternative targets holds significant potential for uncovering novel hits, but in the academic setting compound collections are rarely used, and shared, in this way. We present a short guide for collecting small molecules not being actively pursued in group projects (which we term "idlers") to establish an open compound library. We describe how a diverse subset of this library was screened against a panel of pathogens, with the resulting data made publicly available. We hope to encourage other academic groups to develop and share their own libraries of idlers, thereby maximizing the utility of existing resources, enabling new insights, and catalyzing novel research directions through open science.