Dude, Timesplitters 2 had a giant fucking revolver [http://vignette3.wikia.nocookie.net/timesplitters/images/5/57/Grenade_Launcher_TS2.jpg/revision/latest?cb=20110821104750] that shot grenades that split into more grenades. And fireballs. FIREBALLS. It was chaos letting that thing loose in arcade. They simply called it the grenade launcher, though. Got replaced by the flare guns [http://vignette2.wikia.nocookie.net/timesplitters/images/2/27/Flare_Gun_x2.jpg/revision/latest?cb=20110626203204] from the third game, though, in spirit. They were probably more fun to be honest, but TS2's Grenade launcher was always quite the sight to see.
The Enquirer said:
From Timesplitters: Future Perfect, I gotta give the K-SMG a nod. It's a submachine gun that you can attach a rocket to. Honorable mention to the dual flare guns.
This guy gets it. Heck yes to the K-SMG [http://vignette2.wikia.nocookie.net/timesplitters/images/2/2a/K-SMG_x2.jpg/revision/latest?cb=20110805160020], too! Although I liked shotguns more in TS1 (because foes had less health, thereby making them more effective and thus feel more like a stick of instant death) and TS3 (because it was a single, double barrel which felt awesome to use). Soviet Rifle [http://vignette2.wikia.nocookie.net/timesplitters/images/9/90/Soviet_Rifle.jpg/revision/latest?cb=20110805160316] was great too in TS3. Very efficient and had great animations and sounds.
If I was to mention some other games, though...
Baselard [http://vignette2.wikia.nocookie.net/darkcloud/images/8/8a/Baselard.png/revision/latest?cb=20130309201652] from Dark Chronicle. Looks nothing like a Baselard, but it's available at the weapon shop from the moment you get Monica (and a little bit before, I think) so I consider it a starting sword. It looks cool, and it's got a special place in my heart. So special I made a model [http://img15.deviantart.net/44d8/i/2015/299/2/a/2015_10_27_00001_by_headsprouter-d9eicfd.jpg] and modded it into Fallout: New Vegas. It's pretty shitty, but it's my first 3d model.
The AER14 Prototype Laser Rifle [http://vignette2.wikia.nocookie.net/fallout/images/4/49/AER14_prototype.png/revision/latest?cb=20110421193114] from Fallout: New Vegas is pretty cool. Love me a green laser. And a Fallout laser rifle.
Also on the subject of Fallout, the Missile Launcher from Fallout 3 (but moreso its far more useful iteration in NV) is an incredibly satisfying weapon to use. Something felt really heavy about those missiles, which gave them a lot of impact colliding with a Deathclaw's face. I had a good time playing with Annabelle [http://vignette2.wikia.nocookie.net/fallout/images/a/ab/Annabelle.png/revision/latest?cb=20110209031053] in particular.
Thornblade [http://img1.wikia.nocookie.net/__cb20120612193213/elderscrolls/images/b/ba/Thornblade.png] from Oblivion. I don't like the disintegration effect, but when I see that sword I think: "Wow. That's cool, man." [https://youtu.be/EvUwEVlCOTQ?t=4s] Daedric Longsword [http://vignette3.wikia.nocookie.net/elderscrolls/images/d/d1/Oblivion_DaedricLongsword.png/revision/latest?cb=20120529201509] from that game was very cool, too.
In Skyrim, the Forsworn had a very cool and rather strong (considering it's simple to find from the beginning if you're willing to go up against some of the game's strongest bandits for a sec) bow [http://vignette4.wikia.nocookie.net/elderscrolls/images/c/c9/Forsworn_Bow.png/revision/latest?cb=20121105153355] with a very cool design if you ask me. I like me bows keeping their fine wood texture, you see.
THese probably more than a few I fondly remember from Ratchet and Clank. Pyrocitor [http://vignette3.wikia.nocookie.net/ratchet/images/1/12/Ratchet_and_the_Pyrocitor.jpg/revision/latest?cb=20120711003958] or that lovely green-flamed gold Pyrocitor [http://vignette1.wikia.nocookie.net/iriscompendium/images/0/00/0002s_0002_Gold_Pyrocitor_Purchase_WM.jpg/revision/latest/scale-to-width-down/250?cb=20100628053021] come to mind. "Just a flamethrower" I hear you say? Well, you're not wrong.
The crossbow [http://www.wsgf.org/f/u/imagecache/node-gallery-display/contrib/dr/19173/extras/KillingFloor_2012_01_11_18_59_14_938.jpg] from Killing Floor (can't wait to see it in KF2) because crossbows are cool, it had a cool scoped view and it was a great Scrake killer. The Husk Gun [http://media.moddb.com/images/games/1/13/12018/xmas_huskgun.jpg] was great, too. That was what made me play Firebug. It was like Demolitions and Firebug rolled into one...
I think I've gotten a bit carried away. I love my weapons. Almost as much as I like a good monster to fight.
Edit: One more. The Back Scratcher [http://images.akamai.steamusercontent.com/ugc/713035806383806196/D720A3D0FA82F8682462DF62ED9215BFCC5A05DA/] from TF2. I don't need no medics! I just need a big, strong melee weapon to smack people over the head with! TF2's stock shotgun is also my favourite shotgun ever. I won't link an image. It's just a generic single-barrelled pump shotgun. Just envision that in a vaguely cartoonish TF2-ey style...there you go!