I love buying tools. Even if they aren't powered.
I love the utility knife that I picked up for scoring and trimming drywall...
Load it up with some blades, and when one goes dull, press the red "blade release" button, pull out the dull blade, slide back the slider on the top and then push it back out to reveal a new, sharp blade without having to take the darn thing apart.
Of course, then I just take the blade with the one dull end, flip it around and put it back into the storage/loading compartment. Might as well use both ends of the blade until they are both dull.
So cool and less than $11 at Amazon.