I think I'm sensing a bit of a pattern here and both of you are getting to the same thing, Hornet and cbg.
cbg's point, which is a very good one, is that unless you can explain what you mean by "retaliation" and that it falls under a law that protects you, you have no remedy. If you know the owner of your company hates red shirts and you decide to wear red shirts every day to work - which may be the reason for your termination - you wouldn't really have a case. For what? The employer "retaliating" against you for wearing red shirts? Unless there is some protection that may be afforded you, e.g. a constitutional right, state or federal law, other right to work or process that may have been violated (such as union related), you don't really have a case.
The bottom line - a statute of limitations is meaningless (thanks Hornet for providing that answer) if you don't have a "cause of action" which gives you a right to sue the employer, e.g. for racial discrimination.