I have only played (and loved) Fallout 3 and don?t intend to buy New Vegas until its GOTY version is released and i can have the full game and the DLC for less than 100$+ total... off topic for a moment but long story about replay value Etc, erm short..
Ok let?s try this again, my favorite Fallout weapon is probably the Alien Blaster. It?s Marvin the Martian style and the fact it always makes enemies disintegrate on death thanks to the 100% crit rate that also tends to make it a bit over powered, which i also like about it.
In Fallout 3 there?s the Firelance which while slightly weaker also sets them on fire while they disintegrate which makes for a really cool visual effect for the death of your foes, particularly in V.A.T.S. thanks to the slow-mo.
The gun is seriously overpowered at lower levels. With the better criticals perk at higher levels and the other damage boosting Perks and the Cems and foods that boost damage and AP, you can so easily just walk into a room with like 9 enemies and just enter VATS, pick each target and confirm then sit back and watch as each enemy turns into ash.
An extremely close to #1, 2nd, The Experimental MIRV. Need i say anything about the weapon that is a FREAKING NUKE SHOTGUN?
If so, let me say this further statement about the Experimental MIRV, ITS A NUKE SHOTGUN.
Last note referring to the first part about New Vegas, I will likely buy the GOTY when it comes out and also have it listed on Gamefly so it will be played eventually as a rental.
One last thing, i did love Fallout 3 but i do have some issues with it that i felt if fixed could have made it much better. But thats unrelated to what gun i liked isnt it?