Yo dawg, I heard you like emulating, so I put an emulator in your emulator so you can emulate while you emulate.
ClipperDefiance
More or less. I think there are some differences between the Q and K based models, but they're close enough to not require separate ports of Rockbox.
You should look into Rockbox. It's an open source alternative firmware for a variety of portable media players that adds features such as support for more file formats (and it runs Doom). As for which supported players I'd recommend then maybe a flash modded iPod or an AIGO Eros Q or K (also sold as the HIFI WALKER H2, Surfans F20, or AGPTek H3).
It's not open source, but Tumblr is a decent option if you want something fairly easy to setup. Additionally, it can look very professional with a good theme..
As others have already mentioned, Pixelfed is probably your best option for a FOSS solution to your problem.
I spent my ninth birthday at a funeral home because my grandfather died two days earlier.