Yesterday I spoke at the OsgoodePD mini-conference on
1. Federal anti-money laundering law: Proceeds of Crime (Money Laundering) and Terrorist Financing Act. Note that there's also a Quebec law that might be relevant.
2. HST statute: Excise Tax Act.
3. Provincial Consumer Protection Acts, e.g. Ontario's Consumer Protection Act, 2002
4. Gambling provisions of the Criminal Code.
5. Provincial securities laws, e.g. Ontario's Securities Act.
The above is not an exhaustive list of the laws that could be relevant to a technology company working with blockchains, but these statutes (& regulations) crop up time and again in my own work with startups.
Yesterday's conference had a significant focus on the Ontario Securities Act and the Federal US equivalent. If you'd like to watch the conference they'll be rebroadcasting it in April: http://www.osgoodepd.ca/upcoming_programs/critical-issues-blockchain-law/.