Reflection of Margaret Hunt Hill Bridge in seasonal pond of the Trinity River, Dallas. Reflections are nice, but I usually love them more when they show something, like this rock against the reflected bridge.
The key is a nice still day plus a long enough exposure to smooth out all the ripples. Here I used a polarizer (loses 2 stops of light), slow ISO and really small aperture to get this daytime exposure down to almost 3 seconds.
Canon 1Ds Mark III. 70 mm. ISO 50. Polarized. f/32 @ 2.5 seconds.