IP Options Question

[Maciej Soltysiak]

Hi,

i imagine that IP Options like Source Route can be insecure.
But i would like to know more about the rest of the options.
Which of them can be a security threat?
I think someone somewhere said that IP Option NOP (No Operation)
is used by some lame portscanners.
Actually I know almost nothing about them, so if anyone could
put some light on it, or point to good resources I would be glad.

Have a nice day people,
Maciej Soltysiak.