Sorry, I do not speak English good.
Requirements: Fallout New Vegas.
Installation: put Data folder from this archive to Fallout New Vegas folder.
Location: There is a Rocket truck behind Doc Mitchell's house in Goodsprings.
How to use: take this truck, missile ammo and autoarmor near this truck. Then dress autoarmor (it looks like small car), and take from your backpack (from weapons) Rocket truck.
If you stuck in truck during taking it off press "~" and write "tcl" and Enter, ("tcl" again to switch off).
Bugs: It has no animation of wheels; while it is in 3rd person view there is no good view of this car (because it,s big), but you may use any mods for changing camera, or press "~" and in console write "tfc" ("tfc" again to switch off), this command also someone use for better screenshots; sound of motor may be after taking it off - in this situation you need to save the game and load this save.
Sometimes it may be sounds of steps, so you can lower level of step sound in Fallout settings.
p.s. You may also use autoarmor as simple car, I think (probably with different weapons).
OTHER MILITARY AND CIVILIAN MACHINES:
Tank N-1: tank with revolving chassis;
Attack Ship L-2: It can move by land only. Armament: Medium Laser, Front Medium Laser and Heavy Rockets.
Self-propelled gun (SPG) A-1 (with green colour). Radio and optics versions included.
Self-propelled gun (SPG) A-2. Open-type Self-propelled gun with Nellis artillery mounting.
Self-propelled gun A-3 (with grey colour). Gun of this SPG is movable.
Small Truck from Goodsprings.
Takeable plane B-29. Flight with console "tcl" command or you can use different flight mods like http://newvegas.nexusmods.com/mods/37589 or http://newvegas.nexusmods.com/mods/40784.
Light car v1.0. Working headlights (mainly for decoration) and horn added. Also optional colour variants included.
Tank N-2: tank with revolving chassis and big boom small gun. You can also use this gun behind any cover as small howitzer or make SPG without tank turret.
SPG A-4: black-white colour version included.
Miscellaneous:
Funny Rocket Truck. Funny version with big rocket and rocket pipe.
Big Tank - very big funny tank in Goodsprings.
Swimming boat: I don't know how drive it, just drag it by water or stay on it.
Small plane: flight only with console command tcl or by land.
Attack Ship L-2: It can move by land only (or fly with "tcl" console command). Armament: Heavy Laser, Medium Laser and Heavy Rockets.
Optional:
Light car with wooden colour interior. For different optional colour variants.
Light car with green grass colour.
Light car with dynamite colour. Version with blast sound horn included.
Light car with black colour. With some different variants.
Update: Self-propelled gun A-1 v 0.5. Now gun of this SPG is usable for other characters.
After repeated loading (of saves) SPG and other machines acquires new ability: it aside crates, bottles and other things during drive in front of it.
Speed of this machines not so big. For speed increase you can use different mods like http://newvegas.nexusmods.com/mods/42471 or http://newvegas.nexusmods.com/mods/38666.
See also my Laser tank, laser markers and Attack Ship L-4: http://newvegas.nexusmods.com/mods/49607 and mod with Town Light Car (with model from Fallout 3): http://newvegas.nexusmods.com/mods/49325.
Thanks: Bethesda, Obsidian, GECK, NifSkope.