I was thinking of something fun to do with fellow players. 

Cops and robbers :

Set a prize.
1 vs 9.
Join a lobby
Get teleported to a random spot in Varrock.

Logging out during the match, is a loss.
Teleporting is disabled.

It has elements from PvP but also hide and seek.

The goal is simple.
There is one red caped player
And 9 blue caped players.

At the start of a match, the red player is frozen in place. The blue players must go hide in Varrock.
When the timer is ready, the red player has to kill a blue player.
Upon death, the blue player also becomes a red player. Now it's 2 versus 8.

There is a time limit. After a certain amount of time of not being caught, the opposing team blue will win.

The prize is shared between the winning team.