Because the good end cannot be guaranteed, the dubious means must be avoided.

Bitcoin - Useful Links

Wallets
https://blockchain.info/wallet/
Popular on-line wallets.
https://www.bitaddress.org/
Print paper wallets
for gifts or cold storage.
https://rushwallet.com/
Easy & dangerous.
A quick wallet.
Electrum
Your own local wallet.
Blockchain data
https://bitcoinaverage.com/
Prices & charts.
BitEasy
Blockchain explorer.
https://blockchain.info/
An explorer and more.
Exchanges
Kraken
The biggest in Europe.
Bitstamp
UK Exchange
but no £sterling.
Bitcoin intro
bitcoin.org
https://www.weusecoins.com/
Losing your change
Essential reading!
P2P & OTC
https://bitbargain.co.uk/
https://bittylicious.com/
https://localbitcoins.com/
Where to buy and
sell bitcoin locally.
Spending
http://www.wheretospendbitcoins.co.uk/
Where to spend bitcoin.
https://coinmap.org/
A map of bitcoin services.
Receiving
Mycelium Gear
CoinSimple
Banks
Bitpay
Payment processor,
bitcoin debit card.
Coinjar
A bitcoin bank,
Australia & UK.
Circle
A bitcoin bank.
Do you need one?
Miscellaneous
Paper wallet tutorial
Ripple
The next big thing?
Or is that...
Ethereum
Other crypto
Bithomp
Ripple Account Explorer
Ethereum Block Explorer
Ripple Gateway & Wallet