Movies with Victorian-era warships, or just Steampunky goodness 20,000 Leagues Under the Sea (duh, no brainer) Those Magnificent Men in their Flying Machines (not nautical, but very Punk) Around the World in 80 Days Moby Dick - sorta
At work, it's completely dead. Zero going on tonight. zzzzzzz I'm re-reading old threads like this one: 1 Vs 1 Comparison | R/C Warship Combat
The best steampunk movie of all time. I'll also throw in a plug for Hayao Miyazaki's Laputa: Castle in the Sky. It may be a bit more fantastical, but it has some good steampunk elements in the flapters and airships.
Ah, but the duel in Magnificent Men is so very, very, VERY perfect for Steampunk For those of you unfortunate enough to either not have seen or not remember: French officer challenged to duel by German (Prussian) officer. His choice of weapons? Blunderbusses. In Balloons. Tethered over a wastewater treatment pond, no less
How could I forget Iron Sky? Dirigible spaceships launching flying saucer attack craft. It doesn't get more punk than that.