The chapter describes how a searchable corpus of 100 healthcare simulation videos was constructed by students in one university and then used by undergraduates in another. As part of research into bespoke corpora that can be used in cross-university exercises in ELT writing, the chapter describes the results of this interuniversity project which explored the capacity of students in one university to challenge other groups of students to see whether they could describe the hypotheses presented in the corpus materials. The chapter describes the results of this investigation and draws conclusions about future research into ELT use of video corpora.