immune system cells actually share a lot of the same receptor systems as neurons do, and these systems end up influencing each other to significant degree, both ways.
NULL is more of a declaration that 'there is no value', than mathematical value on its own. if you compare NULL with something you don't get false, you get NULL (which is often considered same as false).
some implementations carry the same "uncomparable" logic when checking for unique constraints, while others drop the ball here.
programming language wise, it's kinda like null pointer or float NaN, both of which are also occasionally complained about, eg. indexing maps by float values can do bogus things in case of NaNs.
You definitely shouldn't strip left side of header, as space preceding that is syntax for header splitting over multiple lines at least in email. Not sure if this applies to http though, but some parsers may do that anyway, and some don't.
Just shows how easy it is to be wrong by being lazy with http parsing.
It works pretty similar to cjdns, but implementation is not as crashy in my experience, also some transport protocol differences (ygg uses tcp while cjdns does udp), also DHT routing instead of cjdns supernode stuff.
So while usability is pretty similar, they're pretty different underneath.
Does it actually work well? I tried to play with it a while back and while sharing files appeared to work, actually downloading them from other node didn't go that well..