Is there a historical reason as to why Xoring any alphabetic letter with the space character changes the case of the letter? (i.e., 'a' xor ' ' = 'A', 'F' xor ' ' = 'f', etc...)
Or is this just a coincidence?
(Assuming the characters are ASCII- or unicode-encoded.)
I'm sure it was deliberate that the case could be changed by changing a single bit - it will have made early software much more efficient. The fact that the space character is #32 is irrelevant.