Password Complexity in the Enterprise?

andrewa asks: "What's the deal with passwords in a corporate environment these days? The company I work for has introduced layer upon layer of complexity on passwords over the years, and now it is simply ridiculous. We have to enter a 16 character password each month that cannot compare in any digits to the previous twelve passwords, nor can it be a simple string -- it has to be a mixture of upper- and lower-case characters including numerals and non-alphanumerical characters. What's next? A mixture of non-keyboard accessible characters and several varieties of DNA? It's not like we are even a government institute -- we are a software company that does telecom stuff, for goodness sake. Anyway ... you know what this makes me do? Write it down somewhere. How secure is that? The question is, I think my company is completely anal with the password requirements, what other security policies are in place in other companies that either completely exceed the banality of my company, or -- God forbid -- have a security system that makes sense?"