Wrote a algo here on Quantopian using zlib and based on linear regression (rest is proprietary). Back tested it and the results where pretty good making 80% profit with a little draw down here and there, so I decided to use it to help me pick credit spreads for options on stocks. Currently using it on my site creditspreadmillionaire.com with very good success, and using it mostly as an entry and exit indicator.
Anyone else implemented their Quantopian algos for actual trading?