Want to know how strong your password is? Steve Gibson’s Interactive Brute Force Password Search Space Calculator shows how dramatically the time-to-crack lengthens with every additional character in your password, especially if one of them is a symbol rather than a letter or number. Worst-case scenario with almost unlimited computing power for brute-forcing the decrypt: 6 alphanumeric characters takes 0.0000224 seconds to crack, 10 alphanumeric characters mixed with numbers and a symbol takes 2.83 weeks.
Considering the recent high profile password hacks of LinkedIn and eHarmony, you should take heed and make sure that your passwords are strong. Equally important is not using common passwords. Hackers know people reuse passwords. Once a password is exposed, they will try it at other sites including banking, e-commerce, facebook, etc.