I can't entirely guarantee that they'll absolutely always work exactly as they should, so it's probably not the best idea to use them in anything absolutely mission-critical. That said, they do seem to work fine for me wherever I use them. And if you do find something wrong, open an issue on GitHub and I'll do my best to fix it.
Licence and Usage
These scripts are licensed under the ☺ licence, so basically you're free to use them however you please - feel free to use or modify them in whatever way you like. You don't have to explicitly credit me (but if you do then I won't complain), but just don't pass them off as entirely your own, ok? That's just not cool.
To begin with, because I needed a smallish MD5 that wasn't poorly written (lots of the others out there leaked globals), but nowadays it's pretty much just because I can.
Well, I started out with a mashup of the pseudocode on the respective wikipedia pages for the functions along with helper functions I found somewhere on the internet for converting strings to byte arrays etc, then bashed them every which-way I could with functionally-equivalent rearrangements to make the size smaller however I could think. Just don't try to get me to explain what any of it does any more.
Shout out to RyanC for spotting a couple of bugs where I'd been a moron and over-optimised.