Favorite Guns/Weapons in Shooter Games?

[Millenium]

Gears of War: Retro Lancer
Halo: Well pretty much all guns implemented pre-Reach
Dead Space: Javelin Gun, Contact Beam & one I forgot the name of.

As for vehicles:

Halo: Warthogs
Battlefield: Tanks
Gears: Junker (I loved the feel when driving that thing)