Fancy socks is a silicon valley thing according to this New York Times article since people normally dress down. If everyone is wearing t-shirt and jeans, socks become your differentiator.
<a href="http://www.nytimes.com/2012/02/05/fashion/in-silicon-valley-socks-make-the-tech-entrepreneur.html" rel="nofollow">http://www.nytimes.com/2012/02/05/fashion/in-silicon-valley-...</a>