Another recoloring technique...

[-Dark-]

I figured this one out accidentally a while ago and it's definitely the fastest method I know of. :0

All you need for this is MSpaint and a num pad on your keyboard. Many of you might know this one, but I'm sure this will help some people. (:

-First you choose the color that you want to change. Set this as the main color.
-Set your secondary color to the desired color you want to change to.
-Select the eraser tool and hold down ctrl and the plus sign (+). Note that this will only work with the + in the number pad, NOT the one next to Backspace. Also note that you have to do it in that order (ctrl first).
-Keep holding down those 2 keys and notice your eraser size growing larger. Let it grow as big as you want :>
-When you've finally made your eraser tool gigantic, right click and drag it over your sprites. Only the unwanted color (the color selected as your main color) will change into the color selected as your secondary color.
-???
-Profit.

Maybe there's an easier way to do this. I dunno....but this method is pretty helpful to me. I just hope i explained it well :x

[A.J. Nitro]

Weird. I never knew about making the eraser big. I'll I've been doing was selecting the whole sheet and making the unwanted color transparent, then coloring that to what I want. But what I've been wondering is when you hold down the Ctrl key and choose a color, that big white square at the bottom left of the screen changes to that color. What does that do?

[-Dark-]

Whoa...I never knew about that. Well...it lets you draw in that color if you hold down ctrl while your draw.

could be useful lol

[A.J. Nitro]

I guess I had to experiment with it, but pretty cool!

[Pik]

By the way, if you don't have a Numpad the on-screen keyboard works too.

[KillerAslox]

It doesn't work, so I do it like this:
First select the color you want to change as 2nd color.
Then set the color you want as 1st.
Press Ctrl+A, Ctrl+X, then change the color (same as the 2nd) into the 1st.
Then press Ctrl+V and select transparant.