OP_RETURN limit is 80 bytes (83 bytes if you include the overhead). But the limitation only applies during relaying transaction. Pool/miner could create coinbase transaction or include their own transaction with OP_RETURN with far bigger size, which means it can be used for more complex advertising/labeling.
was it not reduced to 40 bytes, or was that in a dream?
surely it wasn't reduced to 40, then subsequently bumped back up to 80 again?I don't remember the history very well, but the limit is 80 bytes for last few years. See https://github.com/bitcoin/bitcoin/blob/master/src/script/standard.h#L34-L38.
Imagine that ASIC manufacturers have found a parallel application for their devices, which is in demand by millions of consumers, and not by tens of thousands of miners.
The idea would have gained more interest.
The idea would have gained more interest.
The hardware you're looking for isn't ASIC, but FPGA (Field-programmable gate array) which have good performance (compared with CPU/GPU) while can be used for multiple application.