Recently I started drawing people candidly. It's a good way to practice observational drawing without the subject getting self-concious and checking at you frequently. The poses and actions are more relaxed and natural this way as well.
The fun part comes from the challenge this method presents. That is, because they don't realize they're being drawn, they can tend to shift quite a bit. Or leave. So you have to move quickly and pick your targets carefully. Select people who'll be more or less in the same place for an extended period of time, say someone reading or sitting at a computer. Not that hard to find. A really cool aspect is that in a sketch of a group of people drawn candidly, it'll end up as a sort of disjointed timeline shot of the area. By the time you've finished the second person, the first will have moved on, etc.
Thinking that for the next time I do this I'll hop on a bus and sketch passengers or find somebody in a lineup. That'd be a neat image... a single person in several stages of the line.
This last guy is actually a good fourty years younger than he looks. My pencil is secretly a magical aging ray. Ooooo!
