I'm a Canadian, can I participate?
All the trades we make are in US markets. We have many, many, subscribers from Canada, and nobody has reported any issues to us.
If you've already got a brokerage account we highly suggest that you contact them and ask them the specifics involved with trading US markets—specifically US stocks and etfs. Often there is a small foreign currency transaction fee involved with trades made in US dollars. We don't want anyone to be surprised by this, or to find out after the fact that their particular brokerage charges a hidden fee—so please just call them and ask.
We do know that many active traders based in Canada have been happy with Interactive Brokers. We have no affiliation with them, but you may want to check them out if you are looking for a new brokerage for yourself.