Sold instructions on ebay about how to beat a little known tax law [it's now plugged]. A friend went to work for the tax man and in training they were told abou

Sold instructions on ebay about how to beat a little known tax law [it's now plugged]. A friend went to work for the tax man and in training they were told about me and how it's so important to not let these tricks get out, as it could cost the country lots of money. I promptly stopped as I didn't realize I was on their radar! Reverse engineered an algorithm from a huge international company who kept it under lock and key using publicly available data and used it with their competitors. They still have it under lock and key. Bought textbooks at fundraising sales and sold them to university students the next year for a 3000% markup. Others I'd only tell in person :)