Rectangle rectangle = Utilities.GetCellRectangle(
              flyGrid,
              flyGrid.Rows.Items[0],
              flyGrid.Columns.Items[0]);
            Point pointOnScreen = flyGrid.PointToScreen(new Point(rectangle.X + 1, rectangle.Y + 1));

    public static Rectangle GetCellRectangle(NineRays.Windows.Forms.FlyGrid flyGrid, NodeBase node, Column column)
    {
      FlyGridViewPort viewPort = flyGrid.ActiveRootPort;
      int row = viewPort.Rows.GetRowFromNode(node);
      if (row != -1) //node is visible
      {
        int col = viewPort.Columns.GetColumnCellIndex(column);
        if (col != -1)//column is visible
        {
          return viewPort.GetRectangle(viewPort.Bounds, col, row);
        }
      }

      return Rectangle.Empty;
    }