Sandalwood scented oil. Cost me $10 and smells so unique when compared to big brand colognes and perfumes, which is usually just a mix of these base oils anyway. The difference is that using the oil by itself leads to a potent scent. I put it on this morning, and even after 12 hours, the scent is still quite strong.
Frankincense is another oil that smells good. Add myrrh if you want to smell like Jesus. 😛