I did something similar with Ethereum:
d4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3 is the Genensis hash of Ethereum, which is also used as the private key of this address: 0xf7656Eeec49cC7c2DBee3c08c9f203B25F093cDF
The Merkle root of Bitcoin block
229670 f7a9b2306585fb4801e4b61424dd5523c50f18b2b10011583f265b1d70f481ea is the private key of this address: 0xb8629E8E54f393DCAc2990e59887594C94A7E45F
The hash of Bitcoin block
478610 00000000000000000028389f5b592cbf08ca0451c675432f6060f97d8425fe51 is the private key of this address: 0x91f5A4A03614F131B36671006511f75580c4E550 (a user on BitcoinTalk.org used it, I contacted him to change it)
SHA-256 of the Bitcoin Genesis address 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa, which is 31a9d2e8a70a091d65a58d2a08f8833abf5e8fa1d741c5400c538c38668cb83e, is the private key of this address: 0x700683cFcFE580318CB338E1a8AfCe6C25bB8ceB
Some "brain-wallets":
SHA-256: password : 5e884898da28047151d0e56f8dc6292773603d0d6aabbdd62a11ef721d1542d8 : 0xfb35AD702E715E61A3F362C62DA7C1BD235102FC
Keccak-256: 123456789 : 2a359feeb8e488a1af2c03b908b3ed7990400555db73e1421181d97cac004d48 : 0x62F689837da39B1B50aD39D79E924989E340E0bB
Keccak-256: hello : 1c8aff950685c2ed4bc3174f3472287b56d9517b9c948127319a09a7a36deac8 : 0x5ccfa55C29F0522f062E3C15004E35a69dD45F6B
SHA-256: asdf : f0e4c2f76c58916ec258f246851bea091d14d4247a2fc3e18694461b1816e13b : 0x5aF95f4e0803B739E49B1239bB5Fbe91bD058caD
Keccak-256: testing : 5f16f4c7f149ac4f9510d9cf8cf384038ad348b3bcdc01915f95de12df9d1b02 : 0x89112E3aE3D40362373153c9f08D665ED1e39a7c
Keccak-256: spiderman : ed16b5577f12fd01d27e13991713b21024a88f47de0a0cc9683c6b9391636ad9 : 0xE607194804516037b14Aa050584c4e950975b0F3
Keccak-256: knickers : 6f4fb7f3b1f4ba1b2d4ee901fff911e8ab97299dade221706b7ee65d72343c7a : 0x5de7e496AAc28C05b93d05e4449635b08AEB26Bb
Keccak-256: eeee : 6a7eac42970039e18dca0f0dbd37da2b9e1c04d2026fada6125ee7bfc086708a : 0xc4709734FeAafb57F2CB4c3537F2dfB721f5E3DA
Keccak-256: 12qwaszx : 53652a8bf2e5daa4e38965cb1474f651a62cfd01cdd23d9ca3c64d97fd3a4165 : 0xC5989f90f41c2F4dF71076680A597432136bC10d
Keccak-256: 2 : ad7c5bef027816a800da1736444fb58a807ef4c9603b7848673f7e3a68eb14a5 : 0xDCEceAF3fc5C0a63d195d69b1A90011B7B19650D
Keccak-256: 8 : e4b1702d9298fee62dfeccc57d322a463ad55ca201256d01f62b45b2e1c21c10 : 0xe0FC04FA2d34a66B779fd5CEe748268032a146c0
Keccak-256: 14 : 5c4c6aa067b6f8e6cb38e6ab843832a94d1712d661a04d73c517d6a1931a9e5d : 0x00c40FE2095423509B9fd9B754323158Af2310f3
Keccak-256: 123 : 64e604787cbf194841e7b68d7cd28786f6c9a0a3ab9f8b0a0e87cb4387ab0107 : 0xF46b6B9C7cB552829C1D3dFd8FFb11aaBaE782F6
SHA-256: 935 : b064bdba191139689139124101c1c39926326a9b221bd8dfcd603f065c3dc3b8 : 0xc4704D90cE139d919903ABFD8519F6D393c01B4C
SHA-256: 1870 : cf085574d40ec95878b1c306a9b2432d86c05f888edc87a39708000b3e58b5f9 : 0x3e371363C6B77c0819817bFeb8C98D6A4dbc9efE
SHA-256 of an "empty string" e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 : 0x41aD2bc63A2059f9b623533d87fe99887D794847
I didn't check txids of either Ethereum or Bitcoin if they've been used as private keys, didn't check token addresses, contracts, and I only used Bitcoin addresses that currently have some BTC in them, not every address ever used, so there still might be some addresses to be found.
Needless to say, there's nothing in these addresses any more.