ON ITS Folkestone to Boulogne SeaCat service, Hoverspeed (0304 240241) has introduced a special winter same-day return fare of pounds 25 for a car and up to five passengers. The offer is valid any day until 31 March with the exception of 12, 13, 20 and 21 February. For foot passengers, Hoverspeed has a stand-by French Flyer excursion for pounds 1 per person. Normal day returns cost from pounds 8 (pounds 6 for children).