"RANDOM.ORG offers true random numbers to anyone on the Internet. The randomness comes from atmospheric noise, which for many purposes is better than the pseudo-random number algorithms typically used in computer programs. People use the numbers to run lotteries, draws and sweepstakes and for their games and gambling sites. Scientists use them for random sampling and as input to modelling and simulation applications. Artists use them to make art and music. The service has been operating since 1998 and was built and is being maintained by Mads Haahr who is a Lecturer in the School of Computer Science and Statistics at Trinity College, Dublin in Ireland."
It includes everything from a Coin Flipper to a Dice Roller (useful if you don't actually have the dice you need for a game) to an Integer Generator up to 10,000 numbers, with values determined by the user, limits ±1,000,000,000. A Sequence Generator is the same as the Integer Generator except it eliminates duplicates. And there's a lot more.