Russell: Sources of Randomness for Userspace

I managed to improve the entropy-pool problem on a couple of Xen systems I looked after once that needed the entropy for its VM's by using an inbuilt TPM chip, which many motherboards seem to have.
A daemon (I think is came from rng-tools) can read this entropy data and feed it to the pool.
Had no problems with encryption operations blocking after that.
For high-security systems one would definitely want to validate the quality of the TPM RNG data which no doubt varies from manufacturer to manufacturer, but for the purposes I needed at the time it worked perfectly.