I use the Leatherman C305, which apparently is no…
I use the Leatherman C305, which apparently is no longer available. It's the same knife except the body is solid. After buying my first C305, I bought three more. I've given them as gifts and to have as spares.
You have no idea how handy it is to have a flat head and Phillips screw driver in your pocket...cabinet handle needs tightening? Handle on the frying pot a little loose? License plate rattling? Bolt lock on the door a little loose? Was that screw on the back of the computer cranked down a little more than thumb-tight?
Now add the bottle opener for your favorite beer and one hand deployment of the blade and you've got a tool you'll use EVERY DAY. Oh, and the pocket clip keeps it handy so you don't have to fish around in your pocket when you do need it.