The Infinite Noise TRNG is a USB key hardware true random number generator. It uses what I call a “Modular Entropy Multiplier” architecture (previously Infinite Noise Multiplier or FireBug). Besides being simple, low-cost, and fast, it is much easier to get right than other TRNGs. It naturally defends against influence from outside signals, such as radio interference and power supply noise, making it simple to build securely, without requiring an expert in analog design.
Infinite Noise True Random Number Generator – [Link]