Bitcoins value comes from the real assets that are traded. These assets are foremostly illegal drugs, guns, porn and -- financial security under oppressive government. The last one is now much less valuable however, when Chinese government has started clamping down free internet, and bitcoin transactions will be monitored more closely. However now that we have bitcoin derivatives those who are afraid that bitcoin does not represent their moving asset valuation correctly can effect real changes. Therefore it is prudent to assume that bitcoin will settle down to reasonable level. I think the psychologically "reasonable" value is when one bitcoin is comprehensible to average drug dealer in 3rd world countries. I say 1000 dollars is such a number.