PC Engines APU2 offered unmatched flexibility in the sub-$200 x86 segment:
low-power, fanless
open-source coreboot firmware
Intel NICs (vs Realtek)
open schematics
USB, SD, SATA or mSATA storage
ECC RAM
GPIO
TPM and DRTM
3rd party cases for rack/wall mount
supported by Linux, Xen, OpenBSD, FreeBSD, pfSense, OPNsense
They are taking orders until June 2023, for shipment in ~6 months.Alternatives have different feature subsets, https://news.ycombinator.com/item?id=35635900#35636898