I have been using dry highlighters for some years now. They are the best for activating. I make very quick scans and if something catches my eye, i quickly highlight it. These pencils are easy to carry around and you never have to worry about them drying out or anything like that.
I have wooden ones that i sharpen w/ a penknife or any blade handy. A sharpener is no good for many reasons.
They come in different colors and this can also be used creatively for aiding in activating. Say i highlight something that is important. Then i suddenly find a better description. I will use two colors on top of each other. To me this says it's more important than just a plain color.
I do this before MMing stuff b/c i find i MM faster as a result of doing this. I have pencil highlighters everywhere 
