int x = 5;
int y = 10;
List<System.Windows.Forms.PictureBox> objeto = new List<PictureBox>();
for (int i = 0; i < 10; i++, x += 10)
{
PictureBox cuadro = new PictureBox();
cuadro.Width = 5;
cuadro.Height = 5;
cuadro.Location = new System.Drawing.Point(x, y);
objeto.Add(cuadro);
cuadro.BackColor = Color.Yellow;
}
foreach (System.Windows.Forms.PictureBox imagen in objeto)
this.Controls.Add(imagen);