You take on the role of a private Monster Defense contractor.  The United Nations puts out contracts on various monsters and menaces around the world, and your job is to fill these contracts, destroy monsters, and accumulate enough profit to pay for your own private estate on the Moon.

Each monster has a set of stats, showing how nasty it is.  The nastier the monster, the more valuable the UN contract.  However, you’ll only get paid if the monster is defeated.  If you lose the fight, the monster rages on, and you eat the losses.

To defeat monsters, you put together a specialist fighting force, the best of the best.  These come in the form of cards which you can buy (or bid on, if the game is made multiplayer).  These are all be incredibly silly pop-culture references, mixed in with actual army divisions.  Anime mecha, superheroes, Dracula, James Bond, that sort of stuff.  Each card would have stats as well.  When you fight a monster, you’ll choose which of your units will go into battle.  Some units match up better against some monsters.  For example, giant robots are great against things like Godzilla, and not so good against things like Jason (from Friday 13th).  Dr. Evil has his own private army of henchmen to fight off any conventional military forces, but is incredibly vulnerable to espionage units like James Bond.

This could make for a solid boardgame, where player bid against each other for unit cards and contracts.  It could also make a nice single-player browser game.