Small client that I made that can be used to access the OldSchool version of the game. I know that I'm nowhere near as good as most of the programmers lurking on here, but it works for what it's meant to do, and is more of a learning project. I've added the source code into the jar as well if you want to read through it or if there are any changes that you want to make to it.
I know that it refuses to resize itself if you move around the client just as it goes from the loading over to the game, and I don't really know what do about it, but I added a slight fix that changes it to the right size simply by changing the setting for the client to be always on top or not, so just flick that quickly if the sizing messes up.
Client can be found here.