the old GPUs that used to pool mine before the ASIC takeover are great for searching key spaces and permutated dictionaries, but seems the SDR adoption is lacking. traditionally, SDR is narrowband focused, low overhead more than amenable to CPU cycles. very wide band, very high rate, multi-radio SDR setups are just now coming into independent exploration; perhaps then old GPUs can be brought back to utility!
Agreed near-unlimited-width SDR has fun potential, and for cpunks some equally hard to identify/jam/locate encrypted comms that don't interfere with traditional narrow comms. There are some cheap ex-mining FPGA rigs being dumped on the market too now that they're worthless to the majority of their point-and-click owners.
my favorite odd band technical input is still the barcode scanners from decades past which would interpret scanned input and escapes same
http://americanhistory.si.edu/collections/search/object/nmah_892778 https://en.wikipedia.org/wiki/Helium-neon_laser My later unit of this same class of tech still reads UPC's, love the sounds it makes.
as keyboard console entry. factory reset SMS type attacks have been ongoing for so many years, the same mistakes over and over. back then, you could claim innocent times. today, there is just no excuse.
No doubt in part because we forget wisdom of history in favor of new hotness. Will be pretty sad when in 2100 we have to literally rediscover things from scratch because they're lost. ie: "How the fuck did they do that and their hacking tricks." http://thecorememory.com/