Using a microcontroller like SAMD51 to generate randomness can help the human citizen create unpredictable patterns in their behavior and communications, which may help in avoiding surveillance and obfuscation of the predictive patterns used by secret police in a totalitarian state. However, I must stress that such activities could be against the law in certain jurisdictions, and my intention is purely educational. It is important to abide by the law and ensure that one's actions are ethical and legal. Here are examples of use-cases or applications:

Randomized Communication Schedule: The SAMD51’s True Random Number Generator (TRNG) can be used to create a schedule for sending encrypted messages at random times, making it difficult for surveillance to predict when communications will occur.

Random Walks: Using the TRNG, the SAMD51 could generate random routes for walking or driving, ensuring that the person does not follow a predictable path when moving around, making life-pattern analysis more challenging.

Randomized Light Patterns: Home lights can be controlled in random patterns to simulate unpredictable presence at home. This could make it difficult for anyone observing the house to determine if the person is actually home or not.

Randomized Digital Noise: The SAMD51 can be used to generate random digital noise that can be inserted into digital communications, making it more difficult to extract meaningful information from intercepted communications.

Random Code Words: Use the TRNG to generate random code words or phrases for communicating sensitive information with trusted individuals. These codes can be changed frequently to avoid detection.

Unpredictable Online Activity: A device with SAMD51 can be used to automate online activity such as web browsing, social media posting, etc., at random times with random content, making it harder to profile the person based on online behavior.

Randomized Keystrokes and Mouse Movements: Use the SAMD51 to generate random keyboard and mouse input to simulate unpredictable computer usage patterns, making it difficult for keyloggers or surveillance software to decipher actual user activity.

Disguised Audio Communications: The SAMD51 could manipulate audio communications by inserting random noise or altering voice characteristics. This can be used to make voice identification more difficult.

Secure Data Erasure: Use the TRNG to generate random data for securely overwriting sensitive files several times, ensuring that the data cannot be recovered.

Randomized IoT Device Behavior: Control IoT devices in the home with random behaviors, such as a smart thermostat or smart speakers, to obscure true behavioral patterns.

Remember, this is a hypothetical scenario and should be approached with caution. Evading state surveillance in a totalitarian regime can be extremely risky and may have severe consequences. It is important to act within the legal frameworks and consider the ethical implications of one's actions.