If you carry a debit card, put a maximum daily use on it and also associate it with a pin. This gives you a cash reserve and protects your cash as well.
I then use my debit for cash and never bring traveler's checks either. Go to an ATM and request money in the currency of the country you are in. The best deal? It differs from country to country. For pounds, we found the best deals near the train station at the brokers.
