> Has anyone implemented a PIC (16C57) with 256Kbytes of
> dynamic RAM???

You have to be joking.....

> I'm looking into this now - refresh - what a pain...!!!
>

duh, thats what they invented DRAM controllers for.

> Anyway, anyone that has done this, what's my best option?
>

go back to school?

>             -  (pablo@austin.ibm.com)
                                          ^^^^^
                                         ah, that explains everything