I sold skateboard stickers to other kids when I was about 8. My dad would take me to a store where I bought them wholesale and I sold them for about 5-6 times more. When I was like 12 I noticed while at my dad's store (he sold sports' cars autoparts and such) that the guys at the warehouse bought a lot of raunchy jokes comics. They would read them and then pile them up at a corner, never to be touched again. The cleaning lady would then throw them in the garbage bin once they got to a certain height, so I started selling them at school for about 3 times what they originally cost. Sometimes I'd find some nudie mags in there too. I sold those for roughly 5 times their price. I also sold cigarettes to older kids, but had to quit doing that when they caught me. I remember around that time my parents got their first real fight and I used to feel guilty about it, I guess that somehow caused me to pretty much stop my profitable activities.
I haven't really applied any BH methods lately, but I'm here to change that. I'm a gfx and motion designer, and until a couple weeks ago I was creating promos and commercials for a local tv station, as well as web minisites for their campaigns. I plan to somehow incorporate my skills into white, grey and blackhat marketing after I learn a little more from you guys.