Oh, there's lots of them, Jilli. It's quite the trend, these days.

But are any of them at all worth reading? None of the ones I gingerly looked at seemed like it.

Oh, I don't read them, because they're not my thing. It grieves me as a romance writer to say this, but IMO most romances that attempt to cross over into horror or fantasy are weak, weak, weak. The fantastical elements usually are paint-by-numbers and not well thought out. IMHO, anyway. And I've read some really good time travel romances--it's when you throw in the vampires or mystical powers or ancient gods that all the wheels seem to come off.

Me, I'm just doing my humble best to try to write historical romances that are also good, solid, well-researched historical fiction.

Have I skipped too much to offer that the Sharon Lee/Steve Miller Liaden stories are cross-overs (SF/Romance) that work?

Probably.

Will anyone examine how a testosterone-poisoned male such as myself could be lured into the historical/romance market in a similar way?

There is always hope.

I've read a few that mix fantasy or SF with romance that work (but not the Liaden ones, so I'll have to check those out), but I'd agree with Susan that it's not an easy mix. The vampire ones scared me off a bit, so no advice there.

I think Bujold's Vorkosigan SF books have a romantic element (especially the last one, which I seem to remember was dedicated to some Romance authors). I think they work. Bujold had a short story in a collection that was built around authors combining SF/Fantasy and Romantic fiction. Vampiric romances? I don't believe I've read any that were marketed as such. I guess you could play up the star-crossed lovers aspect.

The only vampire ones I've liked are the southern gothic ones and they are horror/romance/mystery.

Admittedly I've only read a couple.

However, I did read a good fantasy from Luna -- it was based on celtic myths/fairy tales and nicely done. Sadly the first part of two.

I think Bujold's Vorkosigan SF books have a romantic element (especially the last one, which I seem to remember was dedicated to some Romance authors). I think they work.

A Civil Campaign was most definitely a romance novel in a sci-fi universe. I'm sad to say I don't remember much of Diplomatic Immunity -- it's the only one in the series that's ever disappointed me.

Barryar and Free Falling (not technically a Vorkosigan novel, but in the same universe) would probably count too. (Assuming Barryar is the one I think it is -- the one where Miles' parents get together.)

The funny part is, I always found the romantic elements interspersed in the Vorkosigan novels to be the least realistic parts of them. (Okay, some of the Mark sections beat them out, but Mark is only in a couple of novels.) It's all a little too perfect and a little too neat, you know? The rape is narrowly averted; attractions between protagonists are never not reciprocated; nobody ever has screaming fights over stupid things like the toilet seat.

At least the tactical parts of the novels are always predicated on "What can go wrong now??" but all the sexual parts seem to be asking what else can go right. A Civil Campaign was particularly egregious in pairing off anybody who had both first and last names.

Have I skipped too much to offer that the Sharon Lee/Steve Miller Liaden stories are cross-overs (SF/Romance) that work?

I've heard good things about these, but haven't gotten around to them myself.

Will anyone examine how a testosterone-poisoned male such as myself could be lured into the historical/romance market in a similar way?

Well, WHEN I'm published (note my self-confidence there!), you have to buy my books, of course! I'm not sure my first book would appeal to the testosterone-poisoned--it's a Regency house party story and practically a Jane Austen fanfic. But the second one has war and death and battles (assuming I can ever learn to write a decent battle scene). And the one I'm planning to write third is a navy story that I'm tentatively planning to work in around the battles of the Nile and Trafalgar.

In general, I've been happier with authors from other genres including strong romantic elements in their mysteries, fantasies, or whatever than with romance authors trying to blend in elements of the other genres I read. However, it's entirely possible I'm missing the good stuff. Most of the romance-other hybrids I've tried have been cases where a favorite author from my preferred romance subgenre, the historical, adds an element of the paranormal or fantastic. I pick it up thinking, "Oh, this sounds so cool!" And then I read it, and think, "Oh, not cool at all. How many fantasy novels has this woman actually READ, to think she can get by with such half-assed worldbuilding?"

Anyway, I've been trying to expand my romance reading beyond the handful of authors I've been reading exclusively for years and years. Market research, and also because I need to do something besides blink blankly when popular authors are discussed at RWA meetings. If I come across any books that belie my claims from last night, I'll be sure to report back here.

IMO most romances that attempt to cross over into horror or fantasy are weak, weak, weak. The fantastical elements usually are paint-by-numbers and not well thought out.

::nod nod nod::

Generally one is better off sticking with fantasy/SF writers who write relationships well, rather than romance writers who try to add fantasy/SF elements.

One of my favourites is Barbara Hambly. The characters in her books are often older adults and the romance, if there is one, is real and complicated.