Reminds me of a somewhat recent project: some old dictionary running on Windows 3.1¹ running on DOSBox running on Windows Vista running on VirtualBox running on Linux. All for having it along other programs of the same type I use.
Or from some years ago, running a SNES game on an emulator on the PS2 mode on a PS3 modded with HAN (which doesn't allow homebrews). It was running in glorious ~80% speed.
¹ Repurposed from a previous install, and copying the system from its previous storage was an adventure on its own "<.<