What speedwalker/map modules are out there, and for what cost?

I'd really prefer one that's as up-to-date as possible, and it'd be even better if it implemented addons for scry, scent, etc.

The mudlet mapper is free and fairly bleeding-edge. I recommend you give it a try!

I sell a mapper add-on for Treant, which mimics almost all of the Mudbot mapper behavior and then implements additional tracking on top of that. Details are on my web site.

Nick Gammon made a really nifty graphical mapper module for MUSHclient, too, which I'd like to start using as soon as I'm able to add a lot of the functionality of my current mapper script to it.