I've got the nuke once, but only after newb-toobing.
I catch a lot of flak for doing it, but sometimes I just get so fed up with the campers that I have to do it myself.
When playing high-rise on demolition, come out of the building and head straight for the roof on that little building, half-way to the other side. (It's the one with the big tank on it).
Shoot a newb-tube towards the enemy coming out of the window and quickly shoot the tank to explode it. Run up the ladder, place a claymore at top of ladder and lay down. Using One Man Army, reload your same class. This will now give you a second claymore and reload your newb-tube supplies. Put the second claymore at the top of the ladder, just a foot or so back from your other one.
Now, using the extra explosive damage perk, sit up there (using the exploded tank as cover) and quickly aim and fire the tubes at enemies. lay down on the middle of the roof, right next to the exploded tank and reload your tubes. Repeat Ad nauseam. People will start to get wise and try and bomb their own newb-tube or grenade up there, but you should be 95% covered most of the time. When they climb the ladder, they'll hit the claymores. I get AT LEAST 15 straight kills every time. Usually, get it up around 20, especially with the 5-9-11 kill streaks (predator, harriers, pavelow)
Cheap as crap, I know. But damn it's fun to do every now and again.
I'm exactly what's wrong with this game.
