I recently bought a couple a HomePlug adapters to see if they would get me a more stable network connection over wifi. However, as soon as I connected them and fired up my PC I started getting all sorts of network trouble. DHCP would work, but DNS wouldn’t, leaving me unable to surf the web. I now turns out that all this was due to driver issues with the onboard network adapter on my Asus motherboard. This ‘Attansic’ or ‘Atheros’ adapter has apparently been causing issues for many people.
More Attansic LAN vs. Vista trouble? Kill the power!

I use lots of USB devices. External hard drives, a flatbed scanner, card reader, webcam, etc… But I don’t use all of them very often. I’ve even disconnected the scanner because it has no on/off switch and it makes all kind of calibrating noises when I start my computer. My external hard drive, which I use just once a week to run a system backup, also makes more noise than my PC does and it too lacks a proper power switch. This why I came up with the idea of an USB hub with switches that let you decide which devices you want to start up and which you don’t need.
More Idea: USB hub with on/off switches for each device