4. Pink, red and white. Pink is connected to St. Valentine, whose burial was said to have caused the pink almond tree to blossom. Red is a symbol of passion, warmth and the color of the heart. White symbolizes purity—it's purification those naughty pagans were celebrating, after all.
5. Cupid. The mischievous winged cherub is the Roman God of Love and the son of Venus, the Goddess of Love. Cupid is derived from the Latin word "cupido" meaning "desire"—which your lover should be bursting with on V-Day after you've bestowed him/her with the aforementioned goodies.
There you have it. Now all you cynics know that Valentine's Day wasn't actually invented by card and chocolate companies. We've been celebrating it pretty much the same way for centuries, with cards, presents, and heaps of either love or bitterness, whichever side you're on.