There are some lesser-thought of tools that you may wish to consider adding to your already expanding technical tools kits. They are not expensive, but can make a world of difference in diagnosing and repairing problems:
1.) An extension mirror is an invaluable little tool to save your back and knees. Rather than crawling under a desk to see if a cable is plugged in or if the NIC card lights are flashing, use an extension mirror found in any auto parts store (I like the 2”) to take a glance behind the machine without straining yourself. You may need to use this in conjunction with a good mini flashlight.
2.) A magnetic pickup tool is useful for picking up lost screws and parts that fall on the ground. It is not so useful for reaching inside a computer, which is mostly metal, but can grab screws that bounce under tables or chairs quite nicely. Also found in auto parts stores, they are small and easy to carry. Keep in mind that they will attach to anything metal so you may want to keep them in an eyeglasses case or something similar. Or, just keep it isolated.
3.) A very useful little tool I picked up once was a static eliminator. Costing just over a dollar, you simply place this device near what you want to check. If it flashes, it is detecting and eliminating static; when the flashing stops, you are clear. Between this and anti-static wrist straps, you cannot be too careful. Walking across a carpet can produce up to 12,000 volts of static and a computer component can only handle between 3 and 12, depending on the device. Every precaution helps a little.
4.) A headband flashlight sometimes is just the device you need for crawling into tight spaces in cable closets, inside walls, or behind PC’s. You don’t need it every time, but it is a lot more convenient than trying to hold a flashlight in your mouth when you need both hands. A little pricier than I prefer (less than $20), it is nonetheless a very useful tool which I use about once a month. You may also consider a USB book light for working behind PC’s. They plug into the USB port and stay in place where you move it, freeing your hands to work on the system.
5.) Every try to read the fine print in a user agreement or on a motherboard? I have decent eyesight, corrected with laser vision, but even for me it is difficult sometimes. You can pick up a decent jeweler’s visor for $10 and up, depending on the strength and lighting. They magnify and illuminate at the same time, and some even give multiple lenses for differing strengths. It is not always necessary, but you will know for sure if you have a need.