Not really - I worked on a DSP with 9-bit bytes in the 90's (largely because it was focused on MPEG decode for DVDs, new at the time) largely because memory was still very expensive and MPEG2 needed 9-bit frame difference calculations (most people do this as 16-bits these days but back then as I said memory was expensive and you could buy 9-bit parity RAM chips)

It had 512 72-bit registers and was very SIMD/VLIW, was probably the only machine ever with 81-bit instructions

Mpact 2?

If memory serves, I had a Creative Labs DXR2 that I almost immediately regretted.

PDP-10 could do 9-bit (or 7, or 6) bytes into 36-bit words. It seems like something that would be fun for 1-2 days.