32GB flash drives only require 16 of 16Gb NAND FLASH chips which Samsung has announced. That can fit on a DIMM.
http://www.theregister.co.uk/2005/09/12/samsung_16gb_nand_flash/
Bad blocks can be remapped, much as they are in current drive technology, and highly volatile blocks can be frequently remapped to reduce physical writes against any particular block or placed into a smaller store of battery backed RAM.
Flash Based Laptops, Sooner Than You Think