One of the fun things about working on a tropical plants database is all of the unusual species you run into in the process. One of the odder ones I ran into recently is Boleko (Ongokea gore), a tall (up to 50m) African rainforest tree in the family Aptandraceae.
The fruit is described as sweet but slightly astringent, with a smell reminiscent of apples. The unusual aspect of this tree, however, is its seed oil, which is unusually made of fatty acids containing diacetyl groups. As a consequence, the (inedible) oil doesn't dry at room temperature, but as you heat it up past 200-250°C, it begins polymerizing in a highly exothermic reaction. This speeds up the polymerization process; if heat isn't drawn away fast enough, the seed oil will explode. This aggressive polymerization property make it a useful additive to drying oils, converting them to a hard, wear-resistant, heat-resistant and chemical-resistant coating. It's used industrially to make brake pads, as an additive to silicone, and in advnaced adhesives (one has been patented for use in lithium-ion batteries).