This website contains a sequential database of all 2^256 ethereum private keys, spread out on pages of 128 keys each. The key to every wallet, including Vitalik Buterin's wallet, are hidden in one of the pages.
Ethereum keys generated today: 818,464
Also take a look at more ethereum page statistics.
Ethereum wallets can also contain altcoins. This means you can also find ChainLink, OmiseGO or any of your other favorite altcoins on these pages.
Some people say you're better off buying a lottery ticket, but what do they know? You might hit it big on your first random page.