相逢是缘--yes, u can maintain multiple form....

to use ur own logic to switch them on/off (create/dispose)

1.change ur main method like

[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Form f1=new Form();
f1.Show();

Form f2=new Form();
f2.Show();

Application.Run();
}

2. maintain a collection of forms in ur root class.

3. Event handler to coordinate how to create/dispose form in ur root class

4. Create Delegate use signature of event handler in step 3.

5. use event in ur form to hoopup with event handler in step 3 acting like notifier. u can use interface as a helper if u want.

If u r familiar with concepts like Delegate/Event and observer pattern, u know what i'm talking about.

if u r still not sure the implementation, let me know,i help u do a mock up. Thx~~~