Best bang for the buck for me has been aluminum fix it sticks.
I have ridden down portions of the Tour Divide route 3 years in a row and my loving wife has bought me things for my trip almost every year. My gear selection is extremely minimal only taking tools that might actually be needed. A few years ago for Christmas she bought me fix-it-stix. Two years ago as I was getting my gear whittled down on the island in the kitchen, she saw the Fix-it-stix in the mix and asked if I was taking them. I told her that they were a necessity. She was so thrilled that she had gotten me something that was considered necessary. Last year, after helping my son adjust some things on his bike, I didn't zip up a pocket and they slipped out just South of Spray Lake. I was heartbroken about losing them.