A look at the Parallel class, .Net 4.0's new functionality to simplify multi-threading.

1ParallelTest.cs

class ParallelTest
{
	class TestObject
	{
		public string Name { get; set; }
		public int Number { get; set; }

		public override string ToString()
		{
			return Name;
		}
	}

	private readonly Random _random = new Random((int)DateTime.Now.Ticks);
	readonly List<TestObject> _objects = new List<TestObject>();

	public ParallelTest()
	{
		for (int i = 0; i < 10; i++)
			_objects.Add(new TestObject {Name = generateRandomString(), Number = i});
	}
	
	private static void writeList<T>(IEnumerable<T> t)
	{
		foreach (var item in t)
		{
			Console.WriteLine(item.ToString());
		}
		Console.WriteLine("--------------");
	}

	private string generateRandomString()
	{
		const int stringLength = 10;

		
		StringBuilder randomText = new StringBuilder(stringLength);

		const int asciiA = 65;
		const int asciiZ = 90;
		const int range = asciiZ - asciiA;

		for (int i = 0; i < stringLength; i++)
			randomText.Append((char)(asciiA + _random.NextDouble() * range));

		return randomText.ToString();
	}
}

TestParallelFor.cs

public void TestParallelFor()
{
	writeList(_objects);

	Parallel.For(0, _objects.Count(), forMethod);
	writeList(_objects);

	Parallel.For(0, _objects.Count(), delegate(int i)
	{
		_objects[i].Name = new string(_objects[i].Name.Reverse().ToArray()) + _objects[i].Number;
	});

	writeList(_objects);

	Parallel.For(0, _objects.Count(), i =>
	{
		_objects[i].Name = new string(_objects[i].Name.Reverse().ToArray()) + _objects[i].Number;
	});

	writeList(_objects);
}

private void forMethod(int i)
{
	_objects[i].Name = new string(_objects[i].Name.Reverse().ToArray()) + _objects[i].Number;
}

TestParallelForEach.cs

public void TestParallelForEach()
{
	writeList(_objects);

	Parallel.ForEach(_objects,forEachMethod);
	writeList(_objects);

	Parallel.ForEach(_objects, delegate(TestObject to)
	{
		to.Name = new string(to.Name.Reverse().ToArray()) + to.Number;
	});

	writeList(_objects);

	Parallel.ForEach(_objects, to =>
	{
		to.Name = new string(to.Name.Reverse().ToArray()) + to.Number;
	});

	writeList(_objects);
}

private static void forEachMethod(TestObject to)
{
	to.Name = new string(to.Name.Reverse().ToArray()) + to.Number;
}

TestParallelInvoke.cs

public static void TestParallelInvoke()
{
	Parallel.Invoke(() =>
					{
						Thread.Sleep(1);
						Console.Write("Hello");
					}, 
					delegate()
					{
						Thread.Sleep(1000);
						Console.Write("World");
					}, 
					invokeMethod);
}

private static void invokeMethod()
{
	Thread.Sleep(2000);
	Console.Write("!");
}