Keep in mind the size of the tree matters as well. I have cut some large boxelder and they just snap - the medium and smaller ones will hinge just fine. I have also found that trees that have stringy wood seem to hinge well. Like Stu mentioned Hackberry, Elms, soft maples all hinge well. I have some luck with some hickory as well. Trees that have a high moisture content will stump sprout like crazy as well, willows, sycamore, cottonwood, boxelder, soft maples, and those sort you can leave a tall stump and turn into a shrub if so desired. Sometimes just cutting the entire tree down is the best thing you can do as well - just getting sunlight in there will cause an explosion of cover.
Having a means to help to get the tree to topple will help as well. If you just try to do it with a saw - you have to work with the natural lean of the tree which seems to never be where you want it and you tend to cut more than you really want. Anything in the area of about 18" DBH or bigger that needs to go I just plain cut down, remove the log for firewood if desired and leave the top or move it if desired. Those tend to provide a nice support to drop the smaller hinged trees on to.