Rocket Blower + Lenspen are an awesome combo. I use the blower to remove dust, the brush on the pen to get anything else off and the pens' carbon dust to clean the lens.
exactly what i do. it's the best solution in my mind.
i have the kit of three lenspens. normal lens one, filter one and small viewfinder one.
vital to use rocket blower first to avoid rubbing small damaging particles of stuff around with the lens pen. as long as you make sure you do this the lenspens are perfect.