GQueues of course allows you to assign tasks to others or share an entire list with someone to collaborate. However, sometimes you may want to put a task on a co-worker's queue without having it appear in your own lists or as an assigned task. Here's how to do it:
Every GQueues user is assigned a unique GQueues email address, which can be found in the Settings panel.
You can create a task for yourself by sending an email to this address. The subject line will be converted into the task description and the body of the email into notes. You can use the Quick Add Syntax to set other task properties such as the date, tags and queue.
So if you want to allow a co-worker to create tasks in your account, just give them your unique GQueues email address (to make things fair you may want ask for their address in return!) By adding the address to your contacts and giving it an alias you can then easily create tasks in the other person's account.