When I was a kid I found some compression program on a BBS, that claimed to use "wavelets" to compress even more than was previously thought possible. It turne

When I was a kid I found some compression program on a BBS, that claimed to use "wavelets" to compress even more than was previously thought possible. It turned out it was using a similar trick (but this was in MSDOS, so it was just hiding blocks in unused parts of the disk and storing their addresses in the "compressed" file). I blithely used the tool on some things I had on hand that were taking up too much space, and predictably lost ~all of them. I learned a little bit about information theory that day, and my sneakernet bandwidth was saturated for a while afterwards.