Some places where free Wi-Fi is commonly found as of 2015 are Panera Bread, Marriott Courtyard, Office Depot, McDonalds and the Apple Store. A few more stores to look for free Wi-Fi are Staples and CompUSA.
Panera Bread is one of many restaurant chains that commonly offer free Wi-Fi. Other examples of chains that offer Wi-Fi are Applebees, Burger King, Quiznos, Taco Bell and Starbucks. Some retailers that usually have Wi-Fi are Barnes and Noble, Best Buy, Nordstrom and Target.
Many of these places require an acknowledgement and agreeing to terms of service, but they typically don't require a password. McDonald's tends to have the most consistently fast Internet, while Best Buy is a close second.
Other stores with free Wi-Fi are Grease Monkey and Jiffy Lube. Lowe's and Michaels are another source of free Wi-Fi, as are some grocery stores, such as Whole Foods.
It may also be possible to find free Wi-Fi in airports, laundromats and parks, such as Bryant Park in New York City. Additionally, Bolt Bus and Megabus offer free Wi-Fi to their passengers, as does Amtrak. Gyms and yoga studios are also starting to have Wi-Fi available. Some museums also have the service, as do many courthouses.