I strongly disagree with the #1. In my practice, volunteering allows you to secure a rewarding, easy-to-finish-on-schedule task preemptively, while mundane, troublesome and underappreciated tasks are subsequently assigned to other co-workers.

Also, by volunteering you show the boss you actually care and are always ready to work, making you a valuable and trusty employee. Which other colleagues must earn with hard work.

Pick your preferred tasks early and often! ;)