Memory sketches and other life drawings

I've recently been trying out a new pen and sketching method. I was introduced to the Pentel brush pen by Mark McDonnel. It has taken some getting used to but I think I'm getting better with it. I love it cuz I can get a deep black and different thicknesses out of it. I also came across Marcelo Vignali recently, and one thing he posts on his blog quite often is memory sketches. He will go out without his sketchbook, usually at lunch, and observe people. He will then come back and draw those he observed from memory. This not only pushes your observational skills, but also your caracture and design skills. I'm starting to see a bit of an improvement in my work because of it, so I will definatly keep doing this. Most of these drawings are actually memory sketches, but a few are gesture drawings. I got stuck at a wedding and the mall without my sketchbook this week, which wasn't smart. Weddings and the mall are great places to see all sorts of characters come out, so I decided to do memory sketching in lieu of gesture drawing. Interesting side note, the mountain man was a guy at the mall. He looked like a mountain man-ish dude, so I drew him as a mountain man.