This WP pays tribute to the fact that disruptive advances in particle detectors have often been made possible thanks to developments that had not originally been driven by requirements of specific experiments, but which advanced the intrinsic limits of existing technologies, often in synergy with other fields and industries (Blue-Sky research). The four key projects, which were chosen in December 2021, shortly after the start of AIDAinnova in a competitive selection procedure, have been reviewed mid-term. This milestone reports the status of the projects.