My individual trips to work are a little shy of 16 miles, so roughly 30.5 miles RT. I ride alongside the Merrimack River to the ocean and back at least 2 days a week year round. I've found a wonderful route through rural and sparsely populated residential / farm land most of the way... very few cars.
Hills, yes. I have quite a few. Headwind, yes usually both ways due to the way the sea breeze sets up in the AM vs. the PM. It's a rare day when I can get a tailwind on either leg... Oh well, good training right?
Been doing this since I started my new job last June.
I've got a CAAD7 Cannondale R1000 ( Brooks seat, Gatorskin 25's ) for my nice day bike and a Cannondale Cyclocross Disk X7 with some SKS 45mm fenders for winter use ( Nokia W106 studs ) and for warm weather wet day use ( Gatorskin 28's ). I use a Mi-Newt X2 Dual headlight and a Superflash in the rear when it's dark.
Best time is just a few seconds under 46 minutes and then probably about 1:10 or so on the slowest snowy day during the winter.
Don't carry anything as I bring in all my clothes and lunch, etc. on Mondays and shower at a gym across the street from my office, I'm also lucky enough to be able to park the rig in the office inside.
I actually searched for a job that would be coducive to this routine and it's worked out great! Beats the old 90 mile a day commute through BS traffic and crazy MA drivers; I've lost 2 good VW TDI's due to folks rear ending me while stopped in traffic, did that awful commute for close to 8 years... I'm free