Before the era of modern multi-tools, "Swiss Army Knives" made by Victorinox were the bee’s knees. Just ask MacGyver! And these things still work just as well as before – if you are not ruined by modern times and prefer a good old pocket knife to some gadgets and ratchets slapped onto a pair of pliers, get a Victorinox! This tiny pocket knife will easily travel in your jeans’ clock pocket (that’s the small pocket usually inside your right front pocket).
The Victorinox Classic Alox is a small pocket knife with 5 functions. This tiny thing has less features than the larger models, but this will definitely travel in your pocket with you barely noticing it. You can open taped boxes with this, and use the scissors for getting rid of loose threads, and all sorts of precision cutting.
If you need a bigger pocket knife with more functions such as a corkscrew, a metal saw, and larger blade, check out the Victorinox Ranger!