Many locations across the UK will let players connect seamlessly for free.
http://www.nintendoworldreport.com/news/34459
Nintendo has announced a partnership with the company O2 that will allow free Wi-Fi access to Nintendo 3DS owners at a variety of locations in the UK.
Nintendo 3DS players will be able to connect at many locations including, McDonalds, Debenhams, Pizza Hut, Costa Coffee, House of Fraser, Toby Carvery, as well as public venues such as The O2, Twickenham, Bluewater and the Central London boroughs of Westminster and Kensington & Chelsea.
Users will not have to worry about mucking around with any setup on their systems, just being within the range of the network will automatically connect the system. The Nintendo 3DS system must be updated to the most recent firmware for this to work however.