I do this all the time, though not on purpose. On my server, for instance, I like to sell Desh at 50 creds each in stacks of five, which is at 250c. But lots of people on my server seem to think Desh is worth prices like 200c each, and try to sell them in stacks of three. So, while leveling a toon with strictly Gathering Crew Skills, I'll pick up somewhere between 200-300 pieces of something like Bronzium and sell stacks of five for 500c, when everyone else is trying to sell stacks of three for 1500c. Best part is, I have two Gathering toons doing the same thing, so I can list double the amount what SWTOR limits to one character and make craptons of money. I take pleasure in filling in pages and pages of material, I like to imagine I'm Mr. Burns or Scrooge McDuck
Personally, I have no idea who the hell is buying my stuff anyway, considering the people that actually need it can pick it up off the ground for free. Maybe it's the guys trying to gouge people.
Scavenging and Arch materials are my biggest sellers, followed closely by Underworld Trading.