The Artful Parent has a great post that includes photos and tips of all of their melted bead experiments. At the bottom of her post are links to basic instructions and more. These are made with melted pony-type beads, not melty (Perler, Hama) beads. I think the main concern is the odor and toxicity of the melted beads but this is addressed in her posts along with the recommendation to melt them in a toaster oven outside. I love them all but I think these free-form spirals are my favorite!
Here's a nice variation on the salt dough ornament at The Artful Parent - make lacey ornaments by punching holes with a straw. There's also a version that uses beads to give them a stained glass effect.