When you're using a Netduino, don't...

• Drop a wire across the 'clear flash' contacts
• Send it TCP connection requests before it's booted
• Try to allocate 32768 bytes three times over
• Let it crash with the elements at 100%
• Try to low-side switch something being fed with 9v
• Forget the pull-up resistors on I²C
• Use SPI slave devices that pull up on the clock line
• Short +9v to the +3.3v rail. You'll let out the magic smoke, and nothing you did above will matter now.