Some are as simple as racing stripes, and as complex as high quality photos. I once saw a car that was entirely done in high res flames... A paint job of the same thing would have probably cost more than the price of the car, but the nice thing about a wrap (or any vinyl application), is that it is removable.
I've recently learned that you just have to make sure that the application is done with the right equipment so that whenever you are ready to peel it off, that it doesn't take paint with it.
Typically, they are used for advertisements, but putting a 10" stripe down the top of you vehicle is a more simplified version.
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Hooters Xterra 2002, I think.
2007 SEMA Xterra. FYI: It also has a v8 Titan engine, 5" Calmini lift, 33" BFGs, and a GKN electronic-locking front differential.
A high-quality vinyl will last for 5 to 7 years without fading or peeling. And if you off road at all, it will also protect your paint from pinstriping too.
A word of caution: If you do decide to do this, even if you do it yourself, make sure you know what you're doing. Like I said, the quality of materials and craftsmanship will make a difference when you get tired of it and decide to peel it off.
Here's a video of an Xterra getting a wrap:
Xterra Vinyl Wrap 5 min. 27 secs.