Came here to make a remark about Knuth. Indeed, in TACP vol 1, fascicle 1 (the new MMIX design) he talks about being able to address memory in chunks larger tha

Came here to make a remark about Knuth. Indeed, in TACP vol 1, fascicle 1 (the new MMIX design) he talks about being able to address memory in chunks larger than 8 bits and specifically remarks about the unused bits: "we will find precious use for them later". :)