I just returned from Austria with some great memories. However I was changing lens frequently and I have same spots on my sensor. I tried to clean the sensor with my lens pen and a slightly damp cotton swab. However I can't get 3 spots off.
I have a Canon 60D. Lenses 18-135 and 28 1.8.
Local camera shops charge $125 or so for a complete camera cleaning including the sensor.
What is your best sensor cleaning system that you have used?