I've always loved how gifts are wrapped for television and movies with the box top and bottom separate. It's a quick gift open and it's reusable. You could keep the box for treasures/trickets or use it for a gift you're giving someone else.
I was at the Getty Center in Los Angeles last year and found a couple of lovely posters in their gift shop. I repurposed one of the posters as gift wrap and used it to wrap a box 'hollywood style'.
The poster was a replica of an old french postcard so I went with that feeling and added pastel ribbons, a paper rose, some wooden foliage and faux green berry-type things. Poking around the floral department of craft stores is always a good idea!