The following story happened to me the other day. Nearly at the end of my South East Asia trip, I could not get any money from several ATMs. Staying in a far and foreign country without money and a broken credit card is probably one of many worst case scenarios on a trip or travel.
The solution which instantly comes to mind: Somebody, family or friends at home, could send you money. If you are not currently in the situation, you might end your train of thought with this solution. Unfortunately, this solution requires a bank account or a postal address where your helpers can transfer or ship the money to. Even the the transfer from your own account to a temporary bank account in the foreign country might involve authentication problems, a lot of effort and good will.
Luckily, the seventh ATM I tried worked. However, I imagined how the technology of Bitcoin would have saved my trip. With Bitcoin people can transfer money over the wire on their own. For an introduction into Bitcoin see here. Imagine, you let your brother know about your situation and he is willing to send you Bitcoins over the wire from his computer directly to your computer or smartphone. The transaction only requires small effort and the money is instantly in your digital wallet stored on your computer.
There are some shops, restaurants and bars, which accept bitcoins. However, it is probably better to change to the local currency. Unfortunately, the currency exchange do not accept bitcoins (yet), so you have to exchange the bitcoins on the streets. If you are in a big city, it might not be too difficult to find someone who accepts your selling offer. There are some online market places where you can contact people who buy or sell in specific cities. One of them is LocalBitcoins. I dont want to praise nor bad-mouth the technology of Bitcoin in general, but, in my opinion, this is cleary a big advantage for this rising technology.