Not sure what the requirements are for Lemmy but I’ve used Kimsufi and SoYouStart’s dedicated servers for hosting Minecraft. They’re older CPUs but you can get a lot more RAM than a VPS of a similar price. For more lightweight stuff I’ve used Digitalocean VPSes but there are lots of other providers.

Some boards that use the nice!nano have room to tuck a small battery (I think 110mAh) underneath the controller. If they use the 3 middle pins on the nano though, that’s not an option. Rechargeable coin cells are an option, but for boards with the usual LiPO pouch cells, you’ll probably want some kind of case. Some folks just use double-sided tape to hold the battery to the PCB but I’d rather have some protection.