OP: The BlackBerry supports single page TIFF viewing if emailed to your device (at least on BIS), you can try that.
TIFF files are one of the main formats still used by faxes and copiers when making an electronic version, which is what I'm guessing the OP wants it for (artists still use it as well, but I doubt that's why the OP wants). TIFF can store multiple documents in one file (think like pages of a fax) and is highly suited to black&white scanning purposes - contracts, agreements, publications, white papers and so forth.
Wikipedia:
Tagged Image File Format - Wikipedia, the free encyclopedia
OP, I think your best bet would be to find some sort of "TIFF to DOC" converter and use the new DocsToGo program that comes with OS 4.5 to view them... (I know, you're on 4.2.1 - device upgrade needed)