Re: ... / as a path separator and - as a switch character...
I seem to remember there was a simple hack round about MS-DOS 3.mumble that allowed you to change DOS separators and switches to Unix style ones.
It's too long ago now to remember now whether it was changing the value of a constant flag or changing the arguments of CMP AL, '\' and CMP AL, '/' (or some-such) instructions somewhere in the executable.
Another hack (more a prank than anything useful) was to edit the built-in command table to change one command to the name of a program that a colleague used a lot - the built in command then takes priority in parsing over looking for the executable.
Watching the look of confusion when they were going to have a lunchtime game of LARN and instead get...
ECHO is on.