I've been doodling and trying out some cool markers. They're watercolour markers by STAEDTLER and the set I have comes with a white/clear blending marker. I really like the brush tips these markers have. They keep a fine point but a little bit of pressure gives you a wider tapered line. I get loads of control with these.
The colours in the kit I have are beautiful and vibrant. I hear tell they have a skin tone kit......... I'll have to get my hands on one of those.
Here's my kit. They're the STAEDTLER Marsgraphic Jr Watercolour Brush Tip Markers
Here is the white/clear blending marker in action. The farthest away marker is the black marker. I put down a line with the black marker and blended up with the closer blending tip. I think these are going to make adding depth to my idea book sketches much more fun.