In addition to my storage boxes, I have also mounted an awning, a table, chairs, and a gas can on my Gobi Stealth roof rack:
Awning
The very first thing I mounted to the rack was a pull-out awning. We spend a lot of time on the road either cooking, eating, or hanging out outside the car, so a shelter from the rain and sun is pretty important. Without it we’d be stuck sitting in the car a lot of the time.
I bought the Yakima SlimShady awning, which is solid but fairly lightweight. It’s really easy to set up and put away with 2 people. It’s 6.5′ x 6.5′, which we have found to be plenty big for us, but there are definitely bigger options if you need more space. We generally don’t try to use it if the rain is blowing sideways, but we have tarps we can clip to the sides when we need walls.
Folding Table
Having a decent-sized table makes eating and food preparation a lot more convenient. Most established campsites come with a picnic table, but the more remote ones don’t, and even when there is one, you can’t always get the car close enough to get it under the awning.
We picked up a 2′ x 4′ folding table and strapped it to the front section of the rack with a tie-down strap. It also folds in half to make more space on the rack.
Camp Chairs
The rear bars on my roof rack are spaced perfectly to hold 2 folding camp chairs. I strapped in 2 chairs that I have had forever using two bungee cords and they’re very secure. Some cheap camp chairs are great for sitting around a campfire or under the awning, and they stay clean enough up on the roof inside their sleeves.
Gas Can
We luckily haven’t had to use it yet (despite some close calls), but I keep a few gallons of gas in this Midwest metal Jerry can on the roof just in case. This one holds 5 gallons, and fits snugly between my Plano roof boxes. 5 gallons should be more than enough to get me to a gas station if I do run out of gas (at least in North America).