Bitcoin

Smart Bitcoin Investing Strategies https://www.smartbitcoininvestments.com
Bitcoin Mining Difficulty https://bitcoinwisdom.com/bitcoin/difficulty
Bitcoin Wiki https://en.bitcoin.it/wiki/Main_Page
Bitcoin Original White Paper https://bitcoin.org/bitcoin.pdf
Bitcoin Forum https://bitcointalk.org/index.php
Bitcoin Related Hashes http://en.wikipedia.org/wiki/Cryptographic_hash
Bitcoin Currency Improvements https://en.bitcoin.it/wiki/Bitcoin_Improvement_Proposals