I'm not usually a big fan of live wallpapers, and it takes a pretty good one to make me want to use it. It has to be subtle so I can still see the icons, shortcuts and widgets on my homescreen at a glance, easy on the battery, and not make my phone slow down. Circuitry Live Wallpaper fits that bill. I've got it in blue above for a better picture, but you have a choice of six different color schemes (including light grey on dark grey, greyscale FTW), and each is rendered pixel by pixel to be crisp on your screen and the whole thing has been optimized in a way that keeps my phone feeling snappy and lag-free. The jury is still out on battery life, as I've only been using it for a day, but so far so good. Add in the geek factor of circuitry coming to life on my homescreen, and I think I'll use this one for a while. Circuitry Live Wallpaper is 99 cents in the Market, and your phone will need to be running Android 2.1 (and have Live Wallpapers enabled) to use it. Hit the break for a video, download link and some screen shots.