The Intel iAPX 432 used variable bit length instructions, where instruction lengths could be pretty much anything, completely unaligned with bytes. As you might

The Intel iAPX 432 used variable bit length instructions, where instruction lengths could be pretty much anything, completely unaligned with bytes. As you might expect, this was kind of a mess. The iAPX 432 was designed to be Intel's revolutionary follow-on processor to the 8080 with all sorts of bizarre features such as objects implemented in hardware. However, it fell behind schedule, so Intel created the 8086 as a stopgap processor until the iAPX 432 was ready. Things didn't turn out as expected; the 8086 took over the world and the iAPX 432 was a failure.