Supercharging Your Senses

I've been reading about the leaps us humans have been making in genetic engineering lately. There have been some staggering developments. With the ability to change our DNA, man has opened a whole wriggly can-o-worms. My question is this: If you could enhance JUST ONE of your senses (excluding the sixth) to one hundred times your natural ability, which one would you choose, and why?
If this is in the wrong forum, my apologies. Mods do your thing!

[edit on 28-2-2008 by subliminaut]