You might look at Allegro's 6818 and 5818. Serial to 32 bits in a 40 pin package.
Cascadeable.
> Hello,
>
> One of the designs I am working needs many (100 to 200) outputs pins (0/5V
> signal) controlled by a single mid size PIC. What is the cheapest way (cents
> per output pin) adding output pins to a PIC ?
>
> This is a mass production product but an ASIC is out of question at this
> point.
>
> Speed is not an a primary issue so using reasonable serial communication is
> OK.

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