The VP Components VP-Vice Pedals are fairly sleek in person:
http://www.amazon.com/VP-Components-...H7M/ref=sr_1_1


Or their other ones might be more stylish in person (the black pic is weird but look at the colored pics and imagine black for what it looks like in person):
Amazon.com : VP Components Bike Pedals, Black : Sports & Outdoors


The Specialized Bennies that I use are not overly large, but their appearance is slightly larger than the VP Component ones above.


I initially started going down the route you're talking about, looking for the smallest looking pedals, but then I realized that if they're to small I end up with hotspots on my feet when I ride and I wanted to avoid that. You don't want a pedal smaller than the bottom of your shoe.

If you want to spend more money for less weight, a number of people make super super thin pedals now, here's one:
Tioga MT-Zero Platform Pedals in Tree Fort Bikes Pedals