Calendar

Found the code on this machine and added some comments so you have an understanding on things work here
///ASPX code and client script
<script type="text/javascript">
function ToggleCal(){//Toggle Calendar Visibilty of the calendar control inside the divCal
if(document.getElementById('divCal').style.display=='none')
document.getElementById('divCal').style.display='block'
else
document.getElementById('divCal').style.display='none';
}
</script>
<asp:Label ID="lblDate" runat="server" CssClass="lbl" Text="Click Here To View Calendar"></asp:Label>
                    <div id="divCal" style="position: absolute; right: 380px; top: 330px; display: none;">
                        <asp:Calendar ID="CalBook" runat="server" NextMonthText=" >" CssClass="Cal" NextPrevStyle-CssClass="NextPrev" TodayDayStyle-CssClass="TodayStyle"
                            DayStyle-CssClass="DayStyle" ShowGridLines="true" NextPrevFormat="ShortMonth">
                            <WeekendDayStyle CssClass="WeekendStyle" />
                            <OtherMonthDayStyle CssClass="OtherMonthDayStyle" />
                            <SelectedDayStyle CssClass="SelectedDayStyle" />
                            <DayHeaderStyle CssClass="DayHeader" />
                            <TitleStyle CssClass="TitleStyle" />
                            <DayStyle CssClass="DayStyle" />
                            <NextPrevStyle CssClass="NextPrev" />
                        </asp:Calendar>
                    </div>
///End aspx code
'Start VB.NET Code
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
 Me.lblDate.Attributes.Add("onclick", "javascript:ToggleCal();") 'Plug in the client side script to the label control
End Sub
 Protected Sub CalBook_DayRender(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DayRenderEventArgs) Handles CalBook.DayRender
        Dim dtToday As DateTime = DateTime.Now.ToShortDateString
        If e.Day.Date < dtToday Then 'Check date if its past in the calendar
            e.Day.IsSelectable = False 'dont make past days selectable
        End If
    End Sub
    Protected Sub CalBook_SelectionChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles CalBook.SelectionChanged
        Me.lblDate.Text = Me.CalBook.SelectedDate.ToShortDateString 'show the selected date in the label control

        CalBook.VisibleDate = Me.CalBook.SelectedDate 'make sure the calendar control knows which date is selected when its hidden

    End Sub
---End VB.Net code-

Enjoy

Sammy