The Legacy Edition (the original one before the re-write) can be downloaded at:
WARNING: This software is not suitable for daily-usage as it is (literally) useless. DO NOT try to install this software on your physical computer. It is a waste of time and a risk of damaging your computer (or whatever other device you’re using). The stability of the kernel is not guaranteed. Just use emulators like Bochs, the x86 Emulator or VirtualBox.
Joonyoung Lee's Development Board 