Decomp is a sorta complete decompiler.
It'll tell you it also supports the Alpha, but don't believe it. The generated code can't be recompiled so it isn't terribly useful, but it's a great toy to play with and it does decompile things just fine.
Usage: decomp [OPTION]... < FILE >
Decompile FILE into a complete assembly language file which can in turn be re-assembled.
-o, --output < file > Place output in file. The default is to append .S to the input file name.
-h, --help Print this message.
-v, --version Print version information.
-a, --address Print the address of each instruction.
-c, --opcode Print the opcode of each instruction.
-p, --prefix Print any instruction prefixes.
-d, --debug Print debugging information.
-t, --trace Turn on memory tracing.
-q, --queue-size < size > Adjust the size of the output instruction queue. Only use this if you know what you are doing.
IA-32 specific options:
-s, --style < nasm|gas > Select assembly language style. Not yet implemented.