Here is a pic before and after dragging another window over it:
http://phactor.com/t.gif
My code:
Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs)
Dim r As System.Drawing.Rectangle = e.ClipRectangle
Dim g As Graphics = e.Graphics
Dim p As New Pen(Color.White)
Dim hFont As IntPtr = GetStockObject(17)
Dim hFFont As Font = Font.FromHfont(hFont)
g.Clear(Color.FromArgb(80, 80, 80))
... code that paints my text and lines
g.Dispose()
End Sub