This is a screenshot after playing with the Saleae Logic Analyzer for a few minutes. I attached probes to ground, I2C SCL, and I2C SDA on the microcontroller network and poof, I can inspect the traffic. Above you can see me sending one of the slave microcontrollers a 5 byte command with a 16 bit CRC attached.
I'll be learning how this thing works over the next few days and it should save me lots of debugging when I make silly mistakes. I also hope it will let me hack other devices much faster since I will be able to inspect their I2C, One Wire, or Serial communications :)