Nice series of short tutorials from our friend Enrique Rodben (http://www.enriquerodben.com/) (in Spanish).
Tip #0 - Magic Zoom http://vimeo.com/29053985
Tip #1 - Image Effects http://vimeo.com/47638064
Tip #2 - Histograma http://vimeo.com/48671237
Tip #3 - Intervalometro & Bulb Ramping http://vimeo.com/49885260
Tip #4 - Monitorear Audio http://vimeo.com/51164054