I believe a trust fund lets you put conditions on what would otherwise be a "gift". For instance, if you die and you'd like to ensure your children go to college, you can set that as a condition for their inheritance by setting up a trust with an executor who's job it is to respect those conditions. I am sure that there are limits on said conditions and they could be challenged, but I'm pretty sure that this is a major benefit over just stroking someone a check.
