Couple coloring questions

I'd really love to know how to make black and white icons look like this:


icons are by _impress_me

I know how to make a picture black and white but I'd really love to learn how to make them so well-contrasted as the examples show. It looks like a gradient map was used but I can't be sure.

Also, I would love some suggestions on how to get this coloring as well:



icons also by _impress_me

I use Photoshop CS2.

Sorry for all the questions. I appreciate any help. Thank you! :D