map <c-b> ?\\L<cr>
map <c-w> /\\L<cr>

However, there appears to be a bug when I use it in combination with the 'd' command.  d<c-b> works great but d<c-w> leaves the cursor in the wrong position.  The cursor shouldn't move but instead it appears to move forward the length of the word that was just deleted.  When I try executing the commands directly instead of using the <c-w> mapping it works fine.