SPACE.com - Researchers working with a type of super-cooled helium have made the frigid stuff whistle, an attribute they say might make it the crux of better global positioning systems (GPS) in submarines and airplanes among other things.{br}{br}View the Entire Article (http://us.rd.yahoo.com/dailynews/rss/science/*http://story.news.yahoo.com/news?tmpl=story2&u=/space/20050216/sc_space/whistlingheliumsupercoldsoundmayleadtobettergpsinsubmarines){br}