Hotwire's blind-booking service for hotels—in which you don't find out precisely where in town you'll be staying until your credit card is charged—isn't for everyone. But as flexible travelers, we're fans of using the site, which is owned by Expedia.
Priceline offers a similar service, of course, using a bidding system in which you name-your-own-price.
The trade-off with all of these services is that your hotel's location will be something of a surprise. But in many big cities, it doesn't really matter which neighborhood you're staying in, because you're hopping all over town sightseeing anyway.
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