For my most memorable from the past week I'd have to say it was my shiny Horsea in Pokemon Go. A group of pokemon had spawned near a gym next to the path I was walking on -- they were all potentially shiny, and I checked all of them with no luck. As I was about to walk out of range I noticed there was also a Horsea that had spawned behind the gym which I hadn't seen at first, and when I clicked on it it turned out to be a shiny. Finding any shiny is pretty nice, but this one felt like it almost slipped past me but I managed to get it anyway, so it was especially gratifying.