I got the Brother DCP195C printer working on my Raspberry Pi, and documented the process on Superuser.com.

Lessons learned along the way:

• You can run i386 binaries on ARM with qemu user emulation, as if they were regular binaries.
• Printers make funny noises when they don't receive their input data quick enough.
• The sponge utility is great to fix that and even works in conditions with limited RAM.
• Printer drivers are shellscripts with crazy data munging and a magic binary that somehow converts huge bitmap files into printer instructions.

The binary-only part of the printer driver just munges data from stdin and writes it to stdout. Seems like a good candidate for seccomp_bpf... maybe as the next step. :)