Another usage example

[snshn]

I'm counting the number of users via publish/subscribe method, sending only the total amount of online users.

common.js:

Server = new Meteor.Collection('server'); // Global temporary values

client.js:

Meteor.subscribe('server');

...
    counter: function()
    {
        if( Meteor.status().status == 'connecting' )
            return 'connecting...';
        else if( Meteor.status().status != 'connected' ) // offline or connecting
            return 'offline';

        var total_users = Server.findOne('online') ? Server.findOne('online').val : 1;
        return total_users+' user'+((total_users == 1) ? '' : 's')+' online';
    },
...

server.js:

Meteor.publish('server', function(){
    return Server.find();
});

Meteor.startup(function(){
    Meteor.presences.find().observeChanges({
        added: function(){
            Server.upsert({_id: 'online'}, {_id: 'online', val: Meteor.presences.find().fetch().length || 1});
        },
        removed: function(){
            Server.upsert({_id: 'online'}, {_id: 'online', val: Meteor.presences.find().fetch().length || 1});
        }
    });

});

I had to create a separate collection to make things easier, but there may be a way which would not involve publish/subscribe. I will need that collection to publish more server values later, so probably will stick to that.

I wish there was a way to subscribe to the .length of the Meteor.presences collection, would've made things much more simple.
Great plugin, thanks @tmeasday Ü