Tripods and Hussars is Ty Beard’s set of rules for playing battles set in HG Wells’ War of the Worlds universe.
GASLIGHT is probably the most played set of Victorian Science Fiction miniatures rules available today. The Rivets and Steam site has a page of houserules for the set.
Forgotten Futures is Marcus Rowland’s role playing game of scientific romance. It’s been around for quite a while, having been available on the web for years, before being published by the Heliograph. That company now has discontinued the product, and it again is available on the web. I have a printed copy, and have really enjoyed it. There are plenty of ideas there for miniature wargamers, especially if you like games with a role playing flavor.
Walt O’Hara, tireless advocate of gaming in a gentler time, offers his Le Grande Cirque rules. Walt writes:
The Grand Circuit Races (aka ‘Le Grand Cirque’ by the French and everyone else) is a game of “Conveyance racing” in a weird but whimsical Victorian age loaded with technological possibilities. Players assume the role of racers, competing on behalf of their nation or political faction.
Basement Generals has a general miniature wargaming site with an extensive victorian science fiction section featuring battle reports of their Master of the World Campaign, plus photos of their figures and models.