to carry or not to carry?

This is frequently discuss here with no definite answer as there are two camps carry it, don't carry. Some countries require you to carry id and some say a driver's license is good enough. A copy is only good for proving to the US Consulate that you had passport should your's be lost or stolen. I believe you should carry it BECAUSE it is the only thing that proves you are legal in the country. Besides, if I am carrying it, I always where it is. And there are natural disasters from time to time and I would hate to find my passport in a crumbled hotel. And folks have reported from time to time of leaving the passport in the hotel safe. Pickpockets are more interested in your money so unless your money and passport are rubber band together. This falls into Type 1, Type 2 errors better to have it and not need than to need it and not have it. Now someone will come along and say, "I have never been asked for my passport." Which proves absolutely nothing.

Andre's suggestion may also be more secure. For example, if you scan your credit cards or credit card info and then email the scan to yourself over a secure email connection, it is arguably safer than carrying a piece of paper with the same information somewhere in your luggage or on your person. For example, to send email I use my Comcast email account as the outgoing server. Comcast permits me to connect to it over a SSL or TLS connection. That is, everything between my computer and Comcast is encrypted. If I email myself, I would hope that Comcast doesn't send anything I send to a Comcast address back out on the Internet in an unencrypted connection. Instead, I hope it sits on Comcast's computers in my account. Then if I need to connect overseas, I log on to Comcast and make an encrypted connection and download or print the scan. It may never travel anywhere without being encrypted. Because I'm not 100% sure how Comcast treats the incoming email I sent, or how secure its own computers are, I would probably encrypt the scanned file before sending it, but I'm not sure that is absolutely necessary. At the least, I could also split it up. Half the credit card number in one email, the other half in another. Simple things that make it a bit more difficult for someone to gain access and have the information they need.

Depends on the circumstance and what I consider more secure. Two extreme examples. 1) Staying in a hotel without a safe in the room and I will be doing normal touring. I would carry the passport with me. 2) Staying in a hotel with a safe in the room and I am heading to the beach for the day. Passport goes in the safe.

I would agree that there are a few obvious times when you would not carry a passport like going to the beach or taking a shower.

I'd go for "carry unless there is a compelling reason not to". In any case, something I always recommend people to do is: SCAN ALL your relevant documents (passport, credit cards, relevant paper vouchers if any, health insurance certificate, consent of the parent(s) to take a minor/relative out of the country etc.) and have them stored in your e-mail. This should be mandatory for those travelling alone. It is a simple step that could go long ways should you ever have some catastrophic problem abroad: you simple need an internet connection + printer to get an actual, colored copy of any document. Better, IMHO, than carrying a lot of paper copies you will start getting bored to keep them apart from the main docs.

While it was super annoying, we usually carried our docs with us in a money belt. We knew where our docs were, we knew that no one could break into our room and take them. Just gave us peace of mind. We also needed them quite a bit since we were heading on the train often and moving around. We did take a break in a few cities when we stayed in places that offered a sound room safe but overall felt safer just keeping them tucked in our money belts.

When I'm staying in a hotel, I almost always lock my passport in the safe so long as it looks secure. I would not leave my passport in a hostel, safe or no safe. Then again, staying in hostels kind of gives me the willies, so I'm a smidge biased :P

I carry mine simply because it's your valid ID and shows you're in the country legally (not usually a problem for Americans). While you CAN be checked whenever you cross a border (and CAN also be checked randomly by police anywhere), in my experience it's very rare when traveling between Schengen countries. I like hostels (the clean and quiet ones rather than the party hostels) but my rule of thumb is if it's not in your sight or locked in your locker, assume it will be stolen.

True...when I am staying in a hostel, locker or no locker in the room, I carry the passport on me. But in a Pension or hotel I sometimes leave it there if I am out and about touring the city. No safes in the Pension or hotels, unless it's the hotel safe at the front desk. The so-called party hostels tend to be located near the train station...their one definite advantage, in contrast to the HI hostels. Still it depends on the city. @Catherine... in Vienna, Paris, London it's highly unlikely you'll ever be asked to show the passport if you're just touring around. In all my trips I was never asked by the police, which is proof enough of the chances of having to show it. Have it on you if you are doing a day trip and going by train/bus.