GMT

I cross the prime meridien almost every day. I live 0 degrees 5 minutes east of the prime meridien. I travel to Liverpool Street usually, which is 0 degrees 5 minutes west of the prime meridien. The station closest to the meridien, on my route, is Stratford, which stretches from 7 seconds to 17 seconds west of the meridien.

Of course, crossing the prime meridien has no time-zone related significance like the international date line. But it does mean that I travel to the western hemisphere and back every day.

There is a place near Stratford station called Meridien Square. Should visit it some time.