using twitter like textboxes and giving default text

You can do something like this, create a new form with 2 text boxes on it, this is just a quick demo, you would have to play with the events etc. to get it do to what you want. You would also be better to create a new class that inherits from textbox and then use it anywhere you want the functionality;

Here text box 1 has some default text entered, on a keypress it clear to allow user entry. If the user moves off the control leaving it empty, it repopulates the text field with the default string, likewise if the user enters the form, and it is already been modified the cursors is placed at the end of the users previous entry (you could of course select all text or whatever)

public partial class Form1 : Form
    {

        private String defaultText = "Enter Some Text";

        public Form1()
        {
            InitializeComponent();

            textBox1.Text = defaultText;
        }

        private void textBox1_Enter(object sender, EventArgs e)
        {
            if (textBox1.Text.Equals(defaultText))
            {
                textBox1.SelectionStart = 0;
            }
            else
            {
                textBox1.SelectionStart = textBox1.Text.Length;
            }
        }

        private void textBox1_Leave(object sender, EventArgs e)
        {
            if (textBox1.Text.Length <= 0)
            {
                textBox1.Text = defaultText;
            }
        }

        private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (textBox1.Text.Equals(defaultText))
            {
                textBox1.Text= String.Empty;
            }
        }
    }