Sprite Gen helps you get the background-position, width and height of sprites within a spritesheet as a nice bit of copyable css.
Load the example image, and have a click around. It becomes pretty obvious.
Automated spritesheet generators are pretty cool, but I prefer the control over optimisation and compression you get by making them manually.
However, copying all the positions & sizes from graphics apps wasted a ton of my time, so I made this!