To compile this list of must-have Father’s Day gifts, HKI took into account four things: the gift-that-keeps-on-giving factor, the timeless factor, the cool factor and the will-he-actually-use-it? factor. Under the cool and gifts-that-keep-on-giving umbrella falls the Blade Buddy ($20, getbladebuddy.com) because it puts money into the pocket of the giftee while it saves the environment....