Bokken development has been halted in favour of Iaitō: http://iaito.re
Bokken is a GUI for the Radare project so it offers almost all the same features that Radare has and and some of the Radare's ones. It's intended to be a basic disassembler, mainly, to analyze malware and vulnerabilities.
Currently Bokken is neither an hexadecimal editor nor a full featured disassembler YET, so it should not be used for deep code analysis or to try to modify files with it.
Our main site is located at https://www.bokken.re