See my article, Role-based Security with Forms Authentication[^], for information on how to use a database to store and validate credentials using Forms Authentication, which provides many features over most home-brewed solutions (which are typically pretty insecure if you don't have a lot of experience with security). The .NET Framework 2.0 will make this even easier with pluggable authentication back-ends to various front-ends (like Forms Authentication). For now, you're pretty much left with either extending what's available or implementing your own authentication modules.
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