I am absolutely delighted to note the existance of the Rihannsu1 Encyclopedia, a website devoted to the cool aliens from Diane Duane's novels (and other sources, but they seem to be taking the bulk of their info from her stuff). Someone's even gone to the trouble of reconstructing/inventing more of her Rihannsu language, including a phrasebook...which, however, has a problem.
See, in the book The Romulan Way, Arrhae i-Mnaeha t'Khellian is hru'hfe of a noble house--the title means "servants' manager", she's in charge of running the domestic side of House s'Khellian. One morning she sleeps late, and in her absence two lesser servants, Thue and HHirl, get into a screaming fight in the kitchen over the romance between their children, which apparently neither approves of. Arrhae is on her way into the room when Thue yells, "Eneh hwau'kllhwnia na imirrhlhhse!" This is not glossed for us, but Arrhae's narration calls it an obscenity and she makes an entrance by yanking the kitchen door open and saying, "His father never did that. Certainly not with a kllhe, it would never have stood for it." The glossary at the back of the book defines kllhe as a worm that lives in the pens of domesticated beasts, and I think it's clear that the most likely translation of the phrase is along the lines of "Your father fucks dung-worms!" (Or possibly the verb should be "sodomizes", as HHirl's father pretty clearly had to have sex at some point to produce HHirl2.) The phrasebook has it glossed as "Screw your shitty father!" which, while containing most of the relevant concepts, just doesn't make sense in context. This makes me wary of most of their other language stuff.
But leaving the incredibly geeky nitpick aside, I am delighted to see the site as a whole.
1: The Rihannsu are not to be confused with the "Romulans" of Star Trek: the Next Generation, who seem to have inherited all the bad qualities of the Original Series Klingons3.
2: I think that the difference between Vulcan and Rihannsu attitudes towards pon farr is a lot like Victorian upper-class versus modern-day perception of PMS: for the Vulcans/Victorians, it's a debilitating and mortifying condition that has to be kept quiet and treated with exotic ceremony. For Rihannsu/modern-day Westerners, it's a mildly annoying hormonal upheaval that'll go away on its own. It's also possible that the intensity of pon farr has decreased, given that the Rihannsu are no longer living in the extremely resource-limited environment that presumedly drove its development on Vulcan, but that seems unlikely; two thousand years wouldn't produce a drastic change, especially given that Vulcanoids live so much longer than Terrans.
3: Personally, I think that the DS9 episode "Trials and Tribbleations"--in which the crew of Deep Space Nine interacts with Kirk, the original Enterprise crew, and Klingons from that time period--went about portraying the Klingons (whose makeup changed significantly in going from original Trek to The Motionless Picture) in entirely the wrong way. They did some sort of complicated tapdance about how the "Klingons" we see in the original Trek were really Klingon/human hybrids and Worf gets all "We do not discuss it with outsiders" and it was just dumb. What they should have done was put Michael Dorn in the original Klingon makeup as soon as Worf set foot on the past space station and had no one say a word about it.