The other day I found that there is a .NET wrapper for sqlite. sqlite is a very cool embeddable SQL-92 database engine. It’s a single library that gives you a very fast, very scalable (2TB), single file, multi-user database. I thought the .NET wrapper is exceptionally handy because ADO is slow, and is hard to use (compared to this) and a HUGE overkill for smaller apps. It lets smaller apps have a real relational database without huge numbers of dependencies, complicated installs, or the complexity of ADO. Here is a really quick example program I wrote to try it out:

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using SQLite.NET;

namespace WindowsApplication2
{
    /// <summary>
    /// Summary description for Form1.
    /// </summary>
    public class Form1 : System.Windows.Forms.Form
    {
        private System.Windows.Forms.ListBox listBox1;
        private System.ComponentModel.Container components = null;
        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.Button button1;
        private SQLiteClient db;

        public Form1()
        {
            db = new SQLiteClient("test.db");
            InitializeComponent();
            UpdateList();
        }

        public void UpdateList()
        {
            SQLiteResultSet results;

            results = db.Execute("select name, phone from people order by name;");
            listBox1.Items.Clear();
            foreach(ArrayList row in results.Rows)
            {
                listBox1.Items.Add(row[0]);
            }
        }

        protected override void Dispose( bool disposing )
        {
            if( disposing )
            {
                if (components != null)
                {
                    components.Dispose();
                }
            }
            base.Dispose( disposing );
        }

        #region Windows Form Designer generated code
        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.listBox1 = new System.Windows.Forms.ListBox();
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.button1 = new System.Windows.Forms.Button();
            this.SuspendLayout();
            // 
            // listBox1
            // 
            this.listBox1.Location = new System.Drawing.Point(8, 8);
            this.listBox1.Name = "listBox1";
            this.listBox1.Size = new System.Drawing.Size(136, 199);
            this.listBox1.TabIndex = 0;
            // 
            // textBox1
            // 
            this.textBox1.Location = new System.Drawing.Point(192, 24);
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(120, 20);
            this.textBox1.TabIndex = 1;
            this.textBox1.Text = "textBox1";
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(320, 24);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(72, 16);
            this.button1.TabIndex = 2;
            this.button1.Text = "button1";
            this.button1.Click += new System.EventHandler(this.button1_Click);
            // 
            // Form1
            // 
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.ClientSize = new System.Drawing.Size(408, 349);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.textBox1);
            this.Controls.Add(this.listBox1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.ResumeLayout(false);

        }
        #endregion

        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.Run(new Form1());
        }

        private void button1_Click(object sender, System.EventArgs e)
        {
            db.Execute("insert into people values ('" + textBox1.Text.Replace("'","''") + "','111');");
            UpdateList();
        }
    }
}
http://jclement.ca/devel/dotnet/sqlite.html