0; about 20%; My trading system consists of stockcharts.com for charts, financial statements, and marketedge for their "second opinion".
You don't really need much. I would not characterize BTH as a short play anymore. I have not had a short position for a few months now.
To qualify the 20%, my shorting activities last year (for all positiongs) left me about even. I probably should use tradestation or something similar but I don't have as much time to spend studying charts and researching charts -- hence why I have no longer have short positions.