There are a lot of password generators available in the Internet. Some of them use standard pseudorandom number generators which are unsuitable for cryptographic purposes. Such generators create weak passwords and must never be used! LastBit Password Generator is a cryptographic random generator, so all generated passwords are of good quality. LastBit Password Generator is available as online service as offline application. It uses Microsoft SilverLight technology. If SilverLight is not installed, you'll be prompted to download and install it. You can right click the generator and use "Install Application" option to make this generator available offline through Windows Start menu like a regular application.
Password Generator has Smart Filter: some characters looks very similar, so it's difficult to distinguish them in a random string. For example, letter O and digit 0; 8 and B; l, I and 1. If this checkbox is checked, such characters will never be used in a generated password.
User can choose password length (the longer password, the stronger it (however it is difficult to remember long passwords) and character set: the more characters in the character set, the better. An alphanumerical password is stronger than a letters-only password; all-printable password is better than an alphanumerical one. Passwords that use both lower and upper cased characters are much, much stronger than lower-case only (or upper-case only) passwords.