Come summer, having suffered from sun deprivation for nine-plus months, Seattleites are eager to strip to their skivvies. At Madison Park Beach, that's always a good thing. Owing to its proximity to Capitol Hill and the U District, Madison's shores become crowded with the toned, tanned bodies of gay men and college students. Enjoy the enticing view, and keep in mind that once dusk falls and the lifeguards go off duty, the agenda for many of these babes includes skinny-dipping. It doesn't get much sweeter than that. ?Erika Hobart East Madison Street and East Howe Street, 684-4075