Sensor cleaning beyond a simple "blow job" is something that I have never tackled, in the past usually had any serious cleaning done by professionals, but I know that the day is coming when I should really be prepared to deal on my own with a nasty on the sensor that is more than simply a piece of dust that can easily be blown off with the Giottos Rocket Blower...... I know there are various options:"wet" cleaning vs some other kind of cleaning, etc., etc.....