I am a computer and investing geek from way, WAY back. I read about bitcoin a year ago in Wired magazine and was amused and intrigued. While I was tempted to spend a hundred bucks on a lark (as an early speculator), I just didn't follow up and forgot about the article until a couple of weeks ago. If I had bought in, I would have just sold early and then regretted it so I'm glad I didn't!
I think that the initial run up was driven by fear. Fear of the fed, fear of inflation, fear of economic collapse, etc. etc. Once fear got prices moving fast in the upward direction, greed took hold (tulips) and the speculators entered the market to make a few easy bucks from the next, greater fool. Finally, the general population notices and someone writes a story, the speculators head for the back exits as soon as the "I just bought a bitcoin, look at me!" crowd gets in the front door.
It's interesting to watch but the story hasn't changed. Human nature, printed on a price chart. BTW, if you own any of these things, I would recommend you sell immediately. As Rebel Spy said, the non-techies are now noticing the bubble. The crash can't be far behind.
Now, where did I put my $100000000000000 Weimar Republic note? I need to buy an egg.....