If you want to get ALL your mail - including junk mail - the USPS Premium Forwarding Service is very good. You get your mail sent to you once a week. It costs a small sign up fee and then (I think) $14.95 a week to have it sent wherever you want.
There are a number of other mail forwardeing services which I'm sure others will point out. I just wanted to get the ball rolling with my favorite and the one I use every year. With this one I get all my magazines and my hometown newspaper as well.
Denny & Kylene, Abby (Golden) and Josie (Sheltie),
2004 Itasca Suncruiser 38R, W22, Ultrapower
2012 Jeep Wrangler Sport Unlimited