The standard small X-Acto knife handle design has been around for at least 50 years, and it could use some improvements. This version tightens easily, holds the blade securely (without rotating), is comfortable to hold, and it includes a cap! It also features a large knurled nut for loosening the blade which is not perilously close to the blade itself. And best of all, it won't roll off the friggin' table. Great for holding the ubiquitous #11 blades.

Just slide the core piece into the handle and screw the nut on the end. Loosen the nut slightly and push the core out to insert the blade, and then re-tighten the nut.