Random Integer Generator by Random.org is great for generating true random numbers (based on atmospheric noise) for research. However, it lacks many features, which makes it unsuitable for general purposes. It is not very user friendly for generating quick random numbers. It’s interface is a bit complicated and is suited for only generating research numbers in bulk.
However, it does have some advanced options such as pre-generated randomization based on identifiers, and file generation service with up to 20,000,000 true random values. However, those are paid options.