Here's a cool new control in ASP.NET 2.0, the ImageMap.  You use it like this:

      <asp:imagemap id="Shop"           
        imageurl="Images/ShopChoice.jpg"
        width="150" 
        height="360"
        alternatetext="Shopping choices" 
        runat="Server">    
        
        <asp:circlehotspot
          navigateurl="http://www.tailspintoys.com"
          x="75"
          y="290"
          radius="75"
          hotspotmode="Navigate"
          alternatetext="Shop for toys">           
        </asp:circlehotspot> 
        
        <asp:circlehotspot
          navigateurl="http://www.cohowinery.com"
          x="75"
          y="120"
          radius="75"
          hotspotmode="Navigate"
          alternatetext="Shop for wine">
        </asp:circlehotspot>     
          
      </asp:imagemap>

And the code-behind looks like this:

  void VoteMap_Clicked (Object sender, ImageMapEventArgs e)
  {
    string coordinates;
    string hotSpotType;
    int yescount = ((ViewState["yescount"] != null)? (int)ViewState["yescount"] : 0);
    int nocount = ((ViewState["yescount"] != null)? (int)ViewState["nocount"] : 0);

    // When a user clicks the "Yes" hot spot,
    // display the hot spot's name and coordinates.
    if (e.PostBackValue.Contains("Yes"))
    {
      yescount += 1;
      coordinates = Vote.HotSpots[0].GetCoordinates();
      hotSpotType = Vote.HotSpots[0].ToString ();
      Message1.Text = "You selected " + hotSpotType + " " + e.PostBackValue + ".<br>" +
                      "The coordinates are " + coordinates + ".<br>" +
                      "The current vote count is " + yescount.ToString() + 
            " yes votes and " + nocount.ToString() + " no votes.";
    }
      
    // When a user clicks the "No" hot spot,
    // display the hot spot's name and coordinates.
    else if (e.PostBackValue.Contains("No"))
    {
      nocount += 1;
      coordinates = Vote.HotSpots[1].GetCoordinates();
      hotSpotType = Vote.HotSpots[1].ToString ();
      Message1.Text = "You selected " + hotSpotType + " " + e.PostBackValue + ".<br>" +
                      "The coordinates are " + coordinates + ".<br>" +
            "The current vote count is " + yescount.ToString() +
            " yes votes and " + nocount.ToString() + " no votes.";
    }
    
    else
    {
      Message1.Text = "You did not click a valid hot spot region.";
    }

    ViewState["yescount"] = yescount;
    ViewState["nocount"] = nocount;
  }