Apple iPod Touch 1G (apple-ipt1g)
The iPod can boot Linux with the openiboot firmware which has to be build first. The openiboot firmware is not made for GCC6 and requires a few patches, it's also written for the arm-elf toolchain but it can be built with the arm-eabi toolchain for now which seems to work.
This is also the slowest device yet since it uses a 412 Mhz ARMv6 single-core cpu (Samsung S5L8900) and 128 MB ram. It has also has a PowerVR GPU which can cause trouble with porting.