document.onkeydown = NavigateThrough;

function NavigateThrough (event)
    {
    if (!document.getElementById) return;

    if (window.event) event = window.event;

    if (event.ctrlKey)
        {
        var link = null;
        var href = null;
        switch (event.keyCode ? event.keyCode : event.which ? event.which : null)
            {
            case 0x25:
                    link = document.getElementById ('NextLink');
                    break;
            case 0x27:
                    link = document.getElementById ('PrevLink');
                    break;
            case 0x26:
                    link = document.getElementById ('UpLink');
                    break;
            case 0x28:
                    link = document.getElementById ('DownLink');
                    break;
            case 0x24:
                    href = '/';
                    break;
            }

        if (link && link.href) document.location = link.href;
        if (href) document.location = href;
        }
    }