There is a bike club,les Coeurs Vaillants, based in an area south of Montreal called St-Bruno. They have an agreement with a local army base to use their grounds to maintain a network of single-track trails. The area is relatively compact but there are many trails that criss-cross that are a lot of fun. There isn't a lot of elevation change, just a few short dips and climbs, but the singletrack is within the woods and is nice and twisty.
Our local IMBA chapter (ADSVMQ) has been working with this club to really help with trail building as the area is on clay ground that has a lot of problems draining and can get easily damaged as it takes a really long time for the water to drain away.
Their last project was only started this past weekend, which was to build a pump track in the field not far from the front gate. The pump track was more or less completed yesterday but from what I'm told it still needs some more grooming to ensure that one can properly pump their way through the entire circuit. This was my first time ever on a pump track and really liked it.
Here's a YouTube video I took of a couple of guys riding the pump track.
YouTube Video: http://www.youtube.com/watch?v=xmA5vA18o2o
Here are a few pics: