Random numbers with Arduino

I was looking for a good random numbers function for Arduino. Here is a summary of what i found so far.

Pseudo-random algorithm

An algorithm that produce a sequence of numbers. It will generate the same sequence every time it is used. The built in Arduino library uses this method.

Sampling an unconnected analog input

The TrueRandom library used this approach. Seems to producing more 0s than 1s.

Independent Counter

The probably_random libray uses two counters with independent sources. Seems promising.

TRNG (True Random Number Generator) module

The Atmel SAM3X8E on Arduino DUE has a dedicated block for random numbers. There is a library available for this: advancedFunctions.