The DSL (domain specific language) for defining data formats in ImHex seems really cool. I have never seen a language that mixes logic into definitions of data structures quite like that before.

It wouldn't at all suit a general purpose compiled programming language (the best you can do there is templates or similar), but here it seems really neat. I haven't looked into it (maybe this exists), but I would love to see this DSL as a library or a code generator, to help with parsing custom binary formats in my own programs. This is much easier for this specific purpose than even parser combinators (which is what I would typically use, e.g. winnow in Rust).