We have started to systematically identify periodic variables in the HOYS fields (there will eventually be a general paper about it). Here is the I and R light curve for 2MASS J21375762+5722476, found to have a strong P=7.576d signal. We only show the last two months of data so that the variability timescale of about a week can be seen. The object is a known T Tauri star near the Elephant Trunk Nebula. More detailed analysis is needed to find out if we are seeing the rotational signature of surface spots or orbiting material in the inner disk.