So I was looking through my files and found the document that listed all of the "plugins" (read: mods and DLC) I had for Fallout: New Vegas at the time of uninstallation.
This is a good example of just how much crap you can shove into the game. Keep in mind that a lot of people have even more than I do.
CFWNV.esm
DeadMoney.esm
FalloutNV.esm
GunRunnersArsenal.esm
HonestHearts.esm
LonesomeRoad.esm
OldWorldBlues.esm
CaravanPack.esm
TribalPack.esm
MercenaryPack.esm
ClassicPack.esm
Project Nevada - Core.esm
Project Nevada - Equipment.esm
Project Nevada - Rebalance.esp
Project Nevada - Cyberware.esp
More Perks.esm
Ahzteks Weapon Overhaul.esp
Ahzteks Impact Data (Optional).esp
Ahzteks Muzzle Flashes (Optional).esp
00BulletForBenny.esp
31 New Food Items.esp
50mgPenetration.esp
AG Weapon Reload SFX.esp
ammoingredientsloot.esp
Boon of the Boomers.esp
CASE.esm
CASE-Patch GRA.esp
CASE-Patch HH.esp
CASE-Rebalance.esp
CFW-DLC.esp
CFW-PN-DLC.esp
courierpowerarmor.esp
Project Nevada - Courier 6 Armor Patch.esp
Couriersclothes.esp
DeanTurnaround.esp
Delay DLC - DM + HH + OWB + LR + GRA.esp
DFB - Random Encounters.esm
DLC Weapon Integration - WMX.esp
Fellout.esp
Fellout-OWB.esp
ExplorerExtended.esp
ExplosionsKnockDownAlways.esp
Craft Master.esm
Craft Pack.esm
Craft Pack-Ammo CASE.esp
Craft Pack-Ammo.esp
Craft Pack-Armor.esp
Craft Pack-Chemicals.esp
Craft Pack-Companions.esp
Craft Pack-Cooking.esp
Craft Pack-Craft Master.esp
Craft Pack-Crafting Equipment.esp
Craft Pack-Misc.esp
Craft Pack-Movable Crafting Benches.esp
Craft Pack-Patch DM.esp
Craft Pack-Patch GRA.esp
Craft Pack-Patch HH.esp
Craft Pack-Patch LR.esp
Craft Pack-Patch OWB.esp
Craft Pack-Primer Craft CASE.esp
Craft Pack-Primer Craft.esp
Craft Pack-Rebalance.esp
Craft Pack-Weapons CASE.esp
Craft Pack-Weapons.esp
FireaxeInFirehoseBox - MoreTools.esp
FungalProliferation.esp
GRA - The Right to Bear Arms -Vendors Untouched.esp
HackingInstantRetry.esp
Hire Arcade after For Auld Lang Syne.esp
Improved Sound FX - Merged Major DLCs.esp
Improved Sound FX - Project Nevada.esp
Improved Sound FX - Weapon Sharing Fix.esp
Improved Sound FX.esp
Improved Throwing1.esp
IWR - Rebuilt.esp
IWR.esm
WMXUE.esp
WMXUE-PN.esp
HZNovacCampfire.esp
IntuitiveRealisticCooking.esp
KeepYourStarBottleCaps.esp
Leveled List Organizer.esm
Leveled List Organizer.esp
LFox Bottle That Water.esp
Light My Flare.esp
LLO-Base Partial Patch-Overhaul.esp
LLO-Base Patch-Overhaul.esp
LLO-Base Patch-Vanilla.esp
LLO-Compatibility Patch-CFWNV.esp
LLO-Compatibility Patch-CFWNV-DM.esp
LLO-Compatibility Patch-Dead Money.esp
LLO-Compatibility Patch-Honest Hearts.esp
LLO-Partial Patch-Ahzteks Weapon Overhaul.esp
LLO-Partial Patch-CASE.esp
LLO-Partial Patch-CFWNV.esp
LLO-Partial Patch-Craft Master.esp
LLO-Partial Patch-Craft Pack.esp
LobotomitesWithCosmicKnives.esp
Loot Vehicles.esp
MCL_Weapon_Pack.esp
Merchants Sell Displayed Items.esp
Minimissilelauncher.esp
More Perks Update.esp
More Traits Update.esp
More Traits.esm
NCR Ranger Helmet Neck Cover.esp
Omegared99-M2081.esp
PipBoysToThePeople.esp
PMT - Destructible Ordnance Reduced Ammo.esp
PMT - Explosive Robots.esp
PMT - Honest Hearts Reduced Ammo.esp
PMT - Nastier mines and grenades.esp
PMT - Reduced Ammo and Chems.esp
PMT - Reduced Caps and Item Value.esp
PMT - Reduced World Items.esp
PMT - Rude Awakening.esp
PMT - Slower Reloading No Visible Perk.esp
PMT - Slower Reloading.esp
PMT - Tougher economy.esp
PMT - Tougher Vehicles.esp
RangerPA.esp
Realistic Wildlife.esp
Riot Gear Neck Cover.esp
shadysandsshuffle 10 seconds.esp
SnowGlobePerks.esp
T51b-Manual.esp
Tag Skills Improved.esp
TheCollector.esp
thestripsentrance.esp
TopsToVault21.esp
TrailCarbineMods.esp
Tutorial Killer - Alternative Start.esp
Tutorial Killer - Factions.esp
Tutorial Killer - Project Nevada.esp
Tutorial Killer.esp
TWO BEARS HIGHFIVING.esp
UnderwaterFX.esp
WMR.esm
WMR_DeadMoney_R.esp
WMR_GunRunnersArsenal_R.esp
WMR_HonestHearts_R.esp
WMR_LonesomeRoad_R.esp
WMR_OldWorldBlues_R.esp
WMR_Vanilla_R.esp
WorkingCapPress.esp
WMX-ModernWeapons.esp
WMX-MW-GRA.esp
WeaponModsExpanded.esp
Craft Pack-Patch WMX.esp
DA-PoilicePistol.esp
D.E.I.M.O.S..esm
SomeguySeries.esm
NewVegasBounties.esp
NewVegasBountiesII.esp
Alternative Start.esp
TheInheritance.esp
NCR Rearmed.esp
Readius_NV.esp
rePopulated Wasteland.esm
WMXUE-CouriersStash.esp
xatmosSkillPerks.esp
Shotgun Commando.esp
pnvnvbount1.esp
Project Nevada - Extra Options.esm
ELECTRO-CITY - CompletedWorkorders.esm
ELECTRO-CITY - Highways and Byways.esm
Inventory Access.esm
pnv.esp
pnvprojectnevada.esp
pnvpoweredpowerarmor.esp
pnvprojectnevadarebalance.esp
Project Nevada - All DLC.esp
Jump Fall Fixer.esp
Powered Power Armor.esp
realistic headshots.esp
RasRepairAll.esp
Realistic_Repair_NV.esp
NCR Rearmament v1.5 (Lore).esp
RBDC - HH.esp
RBDC - DM.esp
BarterRepair.esp
WeaponJammingNoReloadJams.esp
RBDC - OWB.esp
RBDC - LR.esp
Project Nevada - Cyberware Additions.esp
Project Nevada - Rebalance Complete.esp
FO3WeaponsRestoration.esp
WMXUE_FO3WeaponsRestoration.esp
M37Ithaca.esp
1911.45ACP.esp
Integration - Couriers Stash+WMX+Shotgun Commando.esp
LeatherBackpack - eng.esp
QS_Blackwolf_NV_Backpackmod.esp
Clean-Deluxe FNV.esm
Ambient Temperature.esm
Detect Traps.esm
Detect Traps - Traponator 4000.esp
Clean-Deluxe FNV.esp
Clean-Deluxe FNV Merge - All DLC.esp
Detect Traps - DLC.esp
ProfessionalListFixDeadMoney.esp
Detect Traps - Perk.esp
Light Step ED-E.esp
PerkEveryLevel.esp
Imp's More Complex Needs - JA - SORTED.esp
Ambient Temperature - IMCNNV.esp
Imp's More Complex Needs.esp
JIP Realistic Weapon Overheating.esp
XRE - CARS!.esp
Quick Trade.esp
Selective Fire.esm
The Mod Configuration Menu.esp
The Weapon Mod Menu.esp
Lucky38Suite_Reloaded.esm
Run the Lucky 38.esm
The Lucky 38 Empire.esp
That's quite a list. How stable was your game with all those mods installed?
No less stable than New Vegas is already (read: not very). Generally you'll never get the chance to see a mod conflict in action because if you don't sort out the load order (they have tools for that and virtually everyone uses them, thankfully), the game won't even make it five seconds past startup without crashing. Many of the popular mods, like Project: Nevada and Weapon Mods Expanded, include patches (or other mods make patches specifically for them) so they can work together.
Thanks to the Nexus (like New Vegas Nexus and Fallout 3 Nexus), all of the Bethesda RPGs have a site loaded down with mods. I use Oblivion Nexus to get stuff for The Elder Scrolls IV, for instance. It's got nearly as much content.
By the way, for anyone wanting to pick up New Vegas: grab it with all the DLC. You can pick up the Ultimate Edition (which has literally all DLC, including the pre-order starting equipment and Gun Runner's Arsenal) for $20 now. It adds way, way more content than you'd imagine that to be worth and you'll be much happier if you splurge slightly for the complete package. You will literally not run out of things to do, especially if you get modded quests. It's also important for modding, since there are many good and interesting mods that require some or all DLC to work.
Edit: Forgot to mention, there's some very good HD mods to pick up if your computer can handle them. New Vegas isn't ugly by any means, but the HD textures turn it into something else entirely. Millenia is a modder that mainly does HD custom guns (his most recent being an L96A1 and a Beretta 92FS), but he's most well known for his
Weapon Retexture Project, which gives perfect HD textures (often taken from photographs of actual firearms) to the guns. Then there's
NMC's Texture Pack, for stuff like roads, buildings, and large objects.
Wasteland Flora Overhaul adds a ton of plants to the wasteland (along with being pretty, this is actually accurate; there can't be dead grass and trees if there weren't recently alive trees, not 200 years after the nuclear apocalypse), and
Nevada Skies is THE weather mod period.