These are some of the things I try to bring with me when I have to fix computers (Hardware or Software) or networks. Most will
be helpful for all types of PC or network troubleshooting/repair. Each persons situation is different and will need tools/softare for the type of work you regularly 
do. Pick an choose from the lists to make your own toolbox for your own situation.
 
         | Hardware/Tools | 
         | A multi-tool (like the leatherman wave) can replace many tools listed below. It will get you out of many jams. | 
         | A set of screw drivers (flathead and phillips) about 4 sizes of each from medium to small sizes. Also, a set of very tiny ones for laptops. | 
         | A set of hex and torx bits. | 
         | Wire cutters and wire strippers. | 
         | Needle nosed and regular pliers. | 
         | Shrink wrap tubing. | 
         | Lighter. | 
         | Magnet on a stick (for retriving screws that fall in tight spaces). | 
         | Regular magnet to keep all of your screws together or just a small container. Heck tape all the screws to the side of the machine. | 
         | Small flashlight (I like the mini-maglight). | 
         | Pocket knife. | 
         | Scissors | 
         | Electric and Duct tape. Also, some super glue could help. | 
         | Measuring tape. | 
         | Voltage/Multimeter. | 
         | Paperclip (for ejecting stuck CD's). | 
         | Plastic jumpers to open and close pins on boards. | 
         | Zip and velcro ties. | 
         | A kit to mount a 3.5-inch drive in a 5.25-inch bay. | 
         | Good known pieces of hardware (w/drivers would help): NIC (PCI and handy USB NIC) and PCI Video card. The more generic (and a little older)
the better so that most OS's have drivers. Also, all other pieces of hardware could come in handy. Hard drive,CDROM,Floppy Drive,mouse,keyboard,etc.  | 
         | Many different types of cables: CAT-5 patch cable (25',15',6'), crossover cable (or crossover box), rollover cable (for cisco routers), IDE cable 
(ATA100 and the ATA33), floppy cable,power cable. | 
         | Pen/Pencil and a pad of paper. | 
         | Can of compressed air. | 
         | Spare floppy disks. | 
         | Cheap (in case it gets broken) laptop (with PCMCIA nic and modem). For downloading anything needed or checking net connections and tons of other 
stuff. | 
         | Punch down tool for patch panels or phone blocks. | 
         | RJ-45 crimper and ends. | 
         | Spool of CAT5E cable and RJ45 ends. | 
         | Outlet polarity and ground tester. | 
         | ATX Power Supply Tester.Antec has a good one. | 
         | RJ-45/RJ-11 cable tester. | 
         | Laptop IDE to 40pin IDE adaptor. | 
         | Dental mirror. | 
         | Forceps and or channel locks. | 
         | Lockpick set. (You never know.) | 
         | Magnifing glass. | 
         | Tweezers. | 
         | Lots of different gender/type changers. Any you can get your hands on like: PS2 keyboard to AT keyboard. PS2 mouse to serial mouse. | 
         | Cable tracer tone generator kit. | 
         | Label maker. |