For technically minded users who aren't afraid of a steep learning curve, GNU Emacs for Win32 will handle Really Big .cr2 and .pz3 files... fast. Vim 6.0 is also very good, though not as fast as fast as Emacs. Both are available for free, but I really mean it about the learning curve: These are essentially Old Testament programmer's editors. I use both because I come from a software development background and have experience with them.

GNU Emacs:

http://www.gnu.org/software/emacs/windows/ntemacs.html

Vim:

http://www.vim.org

At some point I may throw some Vim scripts together to do some of the anti-crosstalk processing people have been talking about.