Here are a few places to search if you want to know whether something is possible in Max:

• Cycling ’74 Forum: Many years of conversation among max users; use the Advanced Forum Search to see of someone else has come across your inquiry
• MaxObjects.com: Excellent database of 3-rd Party development for Max; this are patches and externals made by people outside of Cycling ’74 that do cool and quirky things.
• Jitter Recipe Books by Andrew Benson: A great set of “simple” Max patches for advanced video applications; excellent tutorials for advanced Jitter work.

Here are the patches I made in class today that demonstrate simple motion tracking controlling a LED, motion tracking for assessing activity in zones, sensor connected to playback speed and filter parameters of a sound file, sensor connected to servo with recording/playback i.e. memory.

Remember also to download the newest version of Maxuino; throw out the old version (alpha-12) and replace it with the new (alpha-13).  This version allows you to save the settings of your teensy (i.e. serial port, pin-mode, …).