The Wonder Weapons from COD's Zombies.
Well, they're not exactly lore-abiding, but the theme is similar, 50's scifi, and they're considered energy weapons. They actually aren't overpowered at all either.
I actually found these from This video on Youtube here, these mods have been on the Nexus for a short while but they've been removed because the content is ripped.
Only thing I'd change is add some on-hit effects to them in the GECK to make them more like their original counterparts, but other than that I'm loving them.
These 2 look pretty nice too:
Also here's a mod that both retextures the original Laser RCW and adds a unique variant of it, so it does add a new weapon and there was no unique RCW in the vanilla, so it's a nice addition: http://www.nexusmods.com/newvegas/mods/42406/?
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