I suppose if you had one RNG that's 0wned by the NSA, and another that's 0wned by the Chinese MSS, and another by the Russian FSB... and you assume they never ever work together or crack each others' systems, you could XOR their results together.

My current best guess: A Hardware True Random Number Generator installed on one server combined with entropy broker to commingle all the entropy pools of the devices on my internal network into the entropy pool of that server and then serve that pool back to all devices acting as an entropy server.

My intent is that if there is a deliberate weakening of certain entropy sources, that my pool is sufficiently different to at least complicate attacks which are guided by information like browser signatures.

Maybe it's not a perfectly secure solution but hopefully my network isn't among the lowest hanging fruit.

Nope. Random.org could be compromised. XORing it with your /dev/random, plus a locally-generated randomness source would work though.

No. You cannot outsource your random number generation unless you have an ultimately trusted third party. The important thing is that nobody knows your random numbers. After all, random.org could be malicious or compromised, too.

A camera and a lava lamp?