Quality software, written by an ape.
MCMap Live
MCMap Live is a Minecraft mapper, like Cartograph for Mac OS X. It is a wrapper for mcmap, Zahl's fantastic and fast isometric Minecraft map renderer. What makes MCMap Live special is that it renders maps in pieces and lets you view them right away in an intuitive, minimalist interface. You can scroll and zoom all around your world and as quick as mcmap can render the chunks, you will see them. Instant gratification!
Minecraft Biome Extractor
MBE is a cross-platform java program that taps into the biome generation code of Minecraft and outputs the color location on the "grasscolor.png" or "foliagecolor.png" for each block of a given map. Thus allowing mapping programs to paint their maps with biome-specific colors.