Bose-Einstein condensation in Rubidium 85 is a macroscopic quantum system where the self interactions can be rapidly adjusted over a very large range. This is done simply by changing a magnetic field near a Feshbach resonance. Condensates near such a resonance show a variety of interesting features, a few of which are actually understood. These include BEC supernova-like explosions ("Bosenovas") and exotic coherent superpositions of atomic and molecular BECs.