http://procssor.com/• Processor is a powerful (and wholly free) CSS prettified that lets you format CSS in the exact way you want. It empowers you to turn your CSS into something that is visually more compelling, and with a minimum of effort at that.
http://csslint.net/• CSS Lint is a tool to help point out problems with your CSS code. It does basic syntax checking as well as applying a set of rules to the code that look for problematic patterns or signs of inefficiency. The rules are all pluggable, so you can easily write your own or omit ones you don’t want.
http://prefixmycss.com/• It’s easy, fast and free.• You can now use powerful CSS3 techniques, and don’t waste your time writing each properties.• First, write your code for your loved browser.• Then, come here, paste your CSS code in the first block, and prefix!• All vendor prefixes are added to your code. You can safely replace your old code.