http://www.mapleleafup.net/forums/index.php
http://www.g503.com/forums/
http://www.canadiangunnutz.com/forum/index.php
http://www.milsurps.com/
These are the only 4 forums on my favorites: anything else I visit when I need them.
2 are for military vehicles and 2 are for military guns, so that makes me a well balanced person.