tremorworks

Here are a few of the non-setting campaigns I've run with HDL:

An action-movie-styled adventure, where the PCs are receiving dreams from an imprisoned ESPer. The ESPer, a young girl, was kidnapped and is being used to locate the Fountain of Youth. Her captors are led by a man who owns a large corporation, and he plans to market the water from the Fountain to the super-rich.

A game based in the Aliens universe. There's plenty of non-game-based info out there (look around for the “Colonial Marines Technical Manual” - everything you could ever want in a game setting is there!), and you can have PCs be marines or mercs, and fight humans or aliens… whatever!

A fantasy setting, with non-humans built using the special rules on creating monsters and other creatures. A lot of “magic” can be simulated using ESPer powers, or just make up new rules for it! The upcoming HDL Options Guide will also include the “official” magic rules.

Anime-style giant robots!! I actually ran a brief campaign based on the anime, “Martial Successor Nadesico.” The robots were basically beefed-up ARCs from Perfect Horizon, and SCom rules were used heavily. I also ran a Macross campaign (since my players got too fed-up with the official Palladium Robotech rules) in the early days of HDL. It worked out well, once I created stats for the valkyries. Now if only my plot hadn't sucked…

The HDL system is certainly adaptable to be used in any setting. Converting from one system to another really depends on the complexity of the original system; in most cases, though, it should be fairly easy based on how HDL was originally set up.

For technology, that's really easy. Most of the rules already exist for that sort of thing. You'd just need to take into account the relative power of weapons and whatnot, and then give them a corresponding damage HDL and TR. For skills, nothing needs to change, although it's important to keep in mind that HDL skills are very specific, so you wouldn't have a skills like “Technology” as it would be far too broad.

The real hurdle comes in with “mutant powers” and whatnot, and anything that presents an inherent change to the system, such as magic. For the most part, I'd say anything non-human and inherent to a creature or character would become a Background, pulled from the characters BGP pool. The HDL Basic Rules cover creating abilities like these, and you can also see some practical examples in Demongate High (Half-demons work the way mutants would) and, to a limited extent, in Perfect Horizon.

At the moment, we're actually working on a conversion guide to translate games from D&D 3.5 to HDL, and it should be available for download very soon!