Ken Wong (Arizona) came through and we talked about using the SDSS photometrically selected luminous red galaxies to identify lines of sight along which there might be large gravitational magnification, to use as fixed, cosmological telescopes. The default plan is to essentially count LRGs on lines of sight; indeed early tests suggest that will be very successful. Jeremy Tinker (NYU) had some great suggestions, not the least of which was this: The most massive clusters actually have a low fraction of their masses in stars, so you should look not for galaxies, but for collections of galaxies that are cluster-like. I think he is probably right; we want to find lines of sight with multiple overlapping clusters. A few clusters might be more valuable than dozens or even hundreds of LRGs.
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