Well, small arms, there will still be no significant change in their principles for a long-long time indeed. The only change will be in the systems itself (like the upgrade of AK-74 to AK-74M to newly Abakan AN-92 and so on). As for science-fiction weapons (it may be a late cold-war time, butt all the newly designs globaly are their ideas given to reality), any laser/plasma weaponry are from physics limit to the energy-capabilities of our sources, so as small arms, no way by my opinion ... butt, there are many projects from the soviet union:
- Mobile anti-aircraft laser instalation - as just one of them on a MZKT-75165 chasis
http://img185.imageshack.us/img185/1443/pic02gh4.jpg, even as a Topol-M looking like laser wehicle (cant find that photo now).
- Laser-tank - as a test of capabilities of that time and technology
http://media.moddb.com/images/groups/1/3/2074/979e867973fc958638a309f921c.jpg - plasma technology in aerial and balistics
- actually plsma emitters on the front-edge of planes to make a plasma-buble to eliminate the air-drag and open the possibility to fly beyond the limitations of airframes (something like gavitation for russian underwater shkval torpedoes to make it fast as a rocket underwater) + at the end of the film - mobile plasma emitters fousing on a certain place to make balistic projectiles (like in the video of MSTA-S) add/or aircrafts to loose wing-lift capability (because plasma has similar capabilities in balistics as vacuum).
Some interesting stuff has been build behind our backs : ) .. butt still, the laser weapons are now in Moscow museum, because it has a significant problem - the need of uninterrupted beaming of the object for to 10 min. !! (because it function is based on heating the warheads or airplane-frames and it acts somewhat lice in a microwawe - just said that to not opening the whole physics about it
The mass and dimensions comes so from the need of an werry eficient powersource and needed energy-capability of the lasers (thats why the tank has so many focussing lenses) to do it even in 10 minute time.
Railgun project of the US NAVY has its big limitations too .. the system needs way to many el.-mag. emittors and an enormous powersource to run it, whyle the dimensions of it would take a half aircraft-carier to fit - not to mention, that it would be fixed !! (another tech. broblem whyte balancing the ship in other positions and during the shoot) Cant shoot much times whyteout changing the railguns components and my favorite - its energyconwerters cant survive sea-water
.. so much to a NAVY-Program. Butt still, it gives enormous potential energy to small objects.
As for the russian plasma-project, is still running both of them
And ad the end - EMPs
- from the 50-ties ... a low-voltage wire, durinng exposion around it makes to change the el.-mag. field of the wire, changing its wavelength frequency making an enormous energy-boom burning el. circles all around. A good way to think about in the game EMP designs for realism and to make people a little more interested in sciences. : )
So my opinion would be in futuristic designs of small arms of various calibers as in our time, witch works well in the space too. (thus the fact, that the vacum-caliber-eficiency should be taken in mind) And in lots and lots of variants of them as in our time : )
(Of course whyte enormous laser and plasma vehicles in mind
)
P.S.: Sorry for the English and the theories, just like to play whyte the head in games.