Half-Life 2 Multiplayer mod.. i can't believe this hasn't been done? Thread

Is there a mod out there that takes the half life 2 universe and turns it into multi-player where its combine vs. rebels but similar to say that of the call of duty games? If there isn't i think it would be a great mod to make especially since a lot of the assets from the game could be used for maps.. player models etc..  You could have different classes and re--use some characters and make new models that are from the half life universe that didnt make it into the second game etc... like the assassin, different weapons etc... and come up with your own ideas.. similar to call of duty you could have it so if you get so many kills in a row you could release headcrabs/ zombies/ manhacks/ hunters/ or it could be a money or point system and you could save up to release such enemies on the rebels or use points to buy better weapons during a game.. not sure what the rebels could have in their arsenal for enemies to send out to attack the combine but i am sure something cool could be thought up. You could make maps that are straight from a half life setting.. and come up with new ideas and expand upon the half life universe. Now don't go thinking i am obsessed with call of duty.. but i am just using that as something to compare this idea to..  There could be different gameplay types etc..

those are similar ideas but not quite what i am saying although i have played jailbreak source. and enjoyed it much not digging the whole idea of it being dinosaurs and robots but still it can be fun.. just wish the weapons and stuff were more based off of a half life 2 setting more.. etc..etc.. i would love to work on a mod like this but obviously seems like no one is interested since nobody has posted besides you haha