I got a $25 Amazon gift card burning a hole in my pocket from Christmas and don't want to buy paper towels or laundry detergent with it.

Just browsing around for something fun I came across Tactical Pens. I always kinda chuckled at these, but for about $20 having a good steel or aluminum dagger in my breast pocket all day seems like a fun purchase. Almost ordered it, but then though you geniuses or maybe even an expert might have a better idea to burn $25 on (plus, it's a slow GD day).

I'm looking for ideas for a self defense/prep item for $25 or less. Ideas?