With Bitcoin now taking a steady dive, buying Bitcoin at 9-15 dollars would be a safe bet. While the virtual currency is still (gray area) legal, buying drugs with them is actually still not legal. Silk Road, an online drug bizarre, hosted on the (once thought secure) Tor network was recently busted and found the owner to be based out of a San Francisco Public Library.
This is why I love this city.
You can find the latest bitcoin value here: bitcoinity