Here is a new little Python script to perform bitwise operations on files (like XOR, ROL/ROR, …). For maximum flexibility, it requires you to provide the operation as a Python expression, like this:
translate.py malware malware.decoded ‘byte ^ 0x10’
This will read file malware, perform XOR 0x10 on each byte (this is, expressed in Python: byte ^ 0x10), and write the result to malware.decoded.
The script has been added to my software page.