Maybe what you're looking for is MorphOS? It can run Amiga binaries.
But, as with AOS4, there's a limited supply of MOS-compatible hardware out there.
If you're interested in MOS, let me know. I'm considering selling mine, as I'm too busy with classic Amigas and C64's these days. It's a Pegasos 1, non-april fix, 128M RAM, 160G hdd, Radeon 9250, mounted in a mini-ITX case with 300W PSU (IIRC). Pretty stable (has crashed only once), has MOS 1.4.5 installed with developer tools. The OS boots in ~2-3 seconds ;-)