The entire idea of killing off ESD is keeping everything at the same potential ... the equipment you're working on, you, the replacement parts, soldering iron, etc. This can be done without any special equipment if you simply use common sense as you work. You have a RAM to install. First, you pick up the sleeve/bag the RAM comes in. That puts you and the bag at the same potential along with the RAM inside the ESD bag/sleeve. You remove the RAM, no potential difference, no damage. Then with the other hand, you grab the chassis of the computer. Now you, the computer and the RAM are at the same potential, no damage. You install the RAM. You're done, no damage.
The static free workstations, ESD mats, wrist straps, etc. are for forgetful folks or assembly lines where speed is paramount in saving money. If I used all the ESD stuff all the time, would I damage fewer parts? I don't know. I've never damaged one without it unless I did something stupid. And that's where the "forgetful" part comes in!
One warning that was alluded to in previous posts. Never, ever ground yourself directly with a wrist strap. Always make sure that there's no less than 1M ohm in series with the strap and ground. If Nigel were to wear a wrist strap without that resistor, he'd kill himself if he touched the chassis of his oscilloscope.
Dean
Dean