C#

protected internal static readonly ... and I wish the list could continue ...

using System;
using System.Threading;
using System.Windows.Forms;

namespace Project1
{
	public class MainForm : Form
	{
		private OtherForm otherForm;

		public MainForm()
		{
			otherForm = new OtherForm();
			Button b = new Button();
			b.Text = "Click Me";
			b.Click += new EventHandler( RunAThread );
			Controls.Add( b );
		}

		private void RunAThread( object sender, EventArgs ea )
		{
			otherForm.Show();
			ThreadWorker tw = new ThreadWorker( otherForm.tb, new OtherForm.UpdateText( otherForm.UpdateTextBoxText ) );
			Thread t = new Thread( new ThreadStart( tw.RunAlotOfIterations ) );
			t.IsBackground = true;
			t.Start();
		}

		[STAThread]
		public static void Main( string[] args )
		{
			Application.Run( new MainForm() );
		}
	}

	public class OtherForm : Form
	{
		public TextBox tb;
		public OtherForm()
		{
			tb = new TextBox();
			tb.Dock = DockStyle.Fill;
			Controls.Add( tb );
		}
		public delegate void UpdateText( string text );
		public void UpdateTextBoxText( string text )
		{
			Controls[ 0 ].Text = text;
		}
	}

	public class ThreadWorker
	{
		private Control c;
		private OtherForm.UpdateText ut;
		public ThreadWorker( Control target, OtherForm.UpdateText del )
		{
			c = target;
			ut = del;
		}
		public void RunAlotOfIterations()
		{
			for( int i = 1; i < 1000000; i++ )
			{
				c.Invoke( ut, new object[] { i.ToString() } );
			}
		}
	}
}

private void loop()
{
    for(i=1; i<1000000;i++)
    {
        f2.textBox1.Text=i.ToString();
        f2.Refresh();
        Application.DoEvents();
    }
}

protected internal static readonly ... and I wish the list could continue ...