[mabster]

My favourite were older embedded systems where 0 was an address you actually do interact with. So for some portion of the code you WANT null pointer access. I can't remember the details but I do remember jumping to null to reset the system being pretty common.

[marshray]

Probably the system interrupt table. Index 0 might reference the handler for the non-maskable interrupt NMI, often the same as a power-on reset.

I recall that on DOS, Borland Turbo C would detect writes to address 0 and print a message during normal program exit.

[ghurtado]

RANDOMIZE USR 0