UK: OCLC: Virtual Reference: Round the clock, round the world
From the article:
Public library users in the United Kingdom now have access to reference librarians 24 hours a day, seven days a week, 365 days a year. Enquire, an online reference service for 86 public libraries, recently became a member of the OCLC 24/7 Reference Cooperative, joining 1,400 other libraries around the world that work together to deliver reference assistance to researchers anytime, anywhere.
Source: OCLC Abstracts