My idea:

Technologically-assisted team tag.

Here’s how it works. The team captains hold a GPS that tracks the enemy team captain. Everyone is wearing belts with those flag-football flags attached on both hips. The teams start in the city, miles apart, and move toward each other with the help of the GPS navigation. The objective is to tag the opposing team captain. But anyone who is tagged (i.e. flagged ripped from belt) is out of action. So you can spread your team out as you get closer to each other and take out the opposition one by one.

Ideally, each team is on hands-free walkie-talkies so they can communicate with other team members and coordinate ambushes and whatnot. I figure teams of about 10 people would be ideal, and I’m thinking the captains need some other name. The “target,” maybe? The “coxswain”? The “Q-Bert”? I don’t know where that came from, but I like it.