Radio 1 Big Weekend
The biggest free concert in Europe they do every May
19th and 20th May 2007 in Preston
Lineup yet to be revealed, but is usually quite good.
Tickets I believe are posted to the address you register with.
But the local people of the area where the Weekend is taking place gets priority, so in this case anyone from Preston will get priority over someone not in Preston but I don't think all tickets are reserved for them only but the majority are I think.
For now you can only register your interest which is worth doing should you not remember later.
Come the end of April you will be e-mailed as to when you can fully register your details to apply for a ticket.