public static class SqlExtensions
{
    public static void QuickOpen(this SqlConnection conn, int timeout)
    {
        // We'll use a Stopwatch here for simplicity. A comparison to a stored DateTime.Now value could also be used
        Stopwatch sw = new Stopwatch();
        bool connectSuccess = false;

        // Try to open the connection, if anything goes wrong, make sure we set connectSuccess = false
        Thread t = new Thread(delegate()
        {
            try
            {
                sw.Start();
                conn.Open();
                connectSuccess = true;
            }
            catch { }
        });

        // Make sure it's marked as a background thread so it'll get cleaned up automatically
        t.IsBackground = true;
        t.Start();

        // Keep trying to join the thread until we either succeed or the timeout value has been exceeded
        while (timeout > sw.ElapsedMilliseconds)
            if (t.Join(1))
                break;

        // If we didn't connect successfully, throw an exception
        if (!connectSuccess)
            throw new Exception("Timed out while trying to connect.");
    }
}