great idea - I did something very similar in April. I was making a personalized notebook for a little boy's 5th birthday (yes, he does write, and very well!), and I needed to cut the cover to fit. That old blade did very well. I hadn't thought of the gift wrap though.
Good idea Maryjo. I keep a jar with used up needles, pins and blades for discard. After reading your tip I fished out the rotary blades to save for future paper projects. Waste not.