There have been so many cartridges come and go over the years for various reasons, mostly due to them becoming outperformed by newer more advanced cartridges. What's a cartridge that was once popular that you would like to see make a comeback? Or that you feel still has a place despite being outdone by other cartridges of similar type. Be it a comeback to the mainstream or one that isn't really used like it was 100+ years ago. For me it would be the 32-20 or really any of the "two numbered cartridges" (25-20, 44-40, 25-35, etc.) with the exception of 45-70 obviously as it seems to be quite popular.