All too often I've seen folks bang their heads against a wall trying to figure out why their HTML or CSS code isn't working correctly. I've done it myself at times. When we find the reason, it's usually a silly typo we made somewhere in the code that's the culprit.
While many code editing software like Dreamweaver has spellchecking as part of its process, it doesn't always catch things like misspellings within path names such as ".../images/freind/" for example.
What other solutions does everyone use to quickly check your code for errors?