I have a bucket full of old Epic 4Gs, the Sprint variant of the Samsung Galaxy S which was also the last mass-produced phone with a good physical keyboard, but it has become very difficult to find software to load on them. Newer builds of LineageOS don't support it and it's pretty much impossible to find old versions of Cyanogen Mod that will run on it. On top of that, it's just too weak of a phone for any newer OSes, though it still has plenty of potential value as an audio player / digital camera / IM machine (thanks to the physical keyboard!) / child's beater phone.
Luckily, I found a cache of old CM10.1 (Ice Cream Sandwich, IIRC) plus G-apps software on one of my old phones that I still use as a digital camera at work, so I figured I'd post it here in case anyone else wants to breathe some life into their old trash-phone. It should flash onto any Epic 4G just fine with Heimdall/Odin. Download link.