Thank you, everybody, for the replies to my first post!

I found my way here recently while investigating ways to make a variable-color laser pointer, which is something I've dreamed of for at least a decade. Just recently I picked up a $1 cigarette lighter/laser pointer combo with which to entertain the dog, and it renewed my interest that had waned over the past few years. Luckily, rog8811 became my new hero just weeks before I hit the net with my queries!

Chemistry's my degree, and while I had a fair dose of physics and quantum mechanics, I haven't managed to incorporate them into my thoughts over the past several years... nice and rusty. These days I'd classify myself as more of a mechanical engineer/entrepreneur.

While the first version of my laser is going to be a copy of rog's one, I still want to understand everything about everything that's going on so I can refine and make my own design. So while reading up on polarization on wikipedia, the single photon thought popped into my mind and I thought I'd see how others modeled this stuff in their heads, hence my post.

For the record, the very first response (by mixedgas) happens to be pretty much exactly the answer I had in my mind when I posted the question. But as often happens with a good question, the answer(s) often lead to even more questions, and I've had a great time investigating them!

Thank you, tocket, for your Stern-Gerlach link. And Snilton, your youtube diffraction link came at a great time, as I was trying to describe that very subject to my girlfriend last night! I've enjoyed all of your responses.