The TassieBot is designed for line following and object detection.

A robotic arm swings a golf club to hit balls

This bot will be able to move down a tunnel, successfully retrieve the desired scroll, and return to the starting point as described in the book- 'Lego Mindstorms NXT the Mayan Adventure'. Build instructions are on page 202 in the PDF. 

This bot will sort long black NXT pegs from long gray pegs, and place them in two separate bins.