Nope.
To be honest, that's something I strongly recommend against. It's a pain, it's a security hole if you're not incredibly careful and it suggests bad design (you wouldn't write a C# class that could operate on any type of object or struct passed in, why do it in SQL?)
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability