The "Sci-Fi Weapons" pages.
Here's my collection of StarTrek artifacts, some I made myself, some I found for sale elsewhere...
My operational knife prop was copied from a StarTrek The Next Generation example. It's close duplicate can be seen hanging on the wall of Warf's quarters on the Enterprise-D in several episodes. It's also very close to the same appearance / function of the model that the actor used to kill Kirk's son in "ST3 Search for Spock". This one is thin aluminum blades in a resin handle. Not good for actual use as a knife, but so light in wieght it's easy to forget it's there.
(Sadly, this knife went missing after use by "Of Gods and Men" film makers > at "New Voyages" in NY.)
Here's a knife custom made for me by the late* K.Russ. {R.I.P.} Heavy aluminum blade in a cast resin handle. It's got brass dust in the resin, and polishes up just like a real metal surface. It had my Klingon name glyph in the handle too! ( I gave J.G.Hertzler this particular knife as a since he played "Koval" in "Of Gods and Men" - and immortalized my glyph as such.)
* On a sad note, The prop artist and founding member of the IKV T'Mar known as K'Russ - has passed away. He died mid-March 2009 from health reasons. His handywork was a reflection of the man. He will be missed on many levels.
Here's a big stainless bladed and aluminum handled (actually useable) Klingon knife prop I ended up with - in partial trade for a Starwars Stormtrooper costume. It's huge, heavy, stays sharp, is really immune to damage, and really works! I've cut steaks with this thing.
This is a stainless steel split-blade Gill Hibben design "made in Taiwan" copy I aquired from an e-bay auction, in a lot of six each. This was eight months before "Star Trek Nemesis" was released to theaters. It's the splitting image of the knife the main character is holding up in the air, as depicted on the official movie poster. Now, it's suddenly hard to find. Hmmm...
I made the Romulan Disruptor from a solid block of balsa wood, and coated it in fiberglass resin after final shaping. The side panels are auto tail light reflector inlaid insideout and later painted gold, and the trigger is a square push switch from RadioShack. The grip on the disruptor is thin hard rubber padding cut to fit and epoxied on. I think I got it fairly correct.
Finished Disruptor >

< After ten coats of paint, before detailing.
Here's a prop I ended up surprised I was able to make: The Klingon Disruptor used for "Enterprise" season 1, show #1. "Klaang" had one of these, and in the show he used it to blow up the grain cilo with the two Suliban agents in it. This is actually an old out-of-manufacture carwash wand!! (Black & Decker "Tornado"?) ...dressed up to closely duplicate the screen used item. I had one of the carwash thingies at home already. I made mine before the first season of Enterprise was over.
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This ... is now that > 
Here's an unauthorized screen grab to show the disruptor I made my copy of...
Other Klingon Disruptors from days gone by...

Here's the four generations of Klingon energy weapons, but not all the versions. I still didn't have the "water fountain tip" disruptor, or the rifle version yet. There's also the Klingon sniper rifle used in "Undiscovered Country". There's a small pistol sized disruptor (a full size version of the 70's Klingon action figure toy accessory) also lurking about in people's collections, but I've never seen it on screen. ( I no longer have any of these items, so I can't take better images ...sorry about that. )
UPDATES TO FOLLOW AT A LATER DATE...