Futuracha Pro is an Open Type Font, originally based on Futura, which includes a large set of ligatures which change dramatically depending on the letter before and after the letter you are typing. This concept is best seen in motion.

Watch the video below and jump to about 1:07 to watch the magic.

The key is the ever-expanding library of ligatures, which you can add to. Futuracha Pro is homing in on the end of its Indiegogo campaign, having long ago reached their original funding goal. This is definitely my favorite new font.