Guys and girls: What do find attractive in the opposite sex, (or same sex if that's what you prefer)

Both personality and physical appearance! Feel free to be descriptive. I know everyone has different tastes, and I’m just curious to see what different people are attracted to!
For example: I find it extremely attractive when a guy is smart and really nice. I’ve always been a little more attracted to shy guys, but not so shy that they won’t talk to you. Outgoing guys are awesome too as long as they are nice! Physically, I tend to be drawn towards guys with brown hair and don’t usually care what color eyes. Strong but not overly muscular guys are attractive. I like it when guys are taller than me, but that’s not hard since I’m five four.