Vivaldi fans lend me your ears for a moment...

Being a fan of Vivaldi's music but not completely fluent I need a little help. There is a piece of music that I am pretty sure is vivaldi playing when you first enter this website http://www.claytonaudio.com could one of you kind folks help me figure out what the title of this piece is so I can add it to my collection and if you have any favorite recordings of it please share it with me :o) Thanks you.