Is my string a number?

I have been recently devoting a-lot of time answering questions on STACKOVERFLOW. Many times, you are just helping and/or teaching younger SQL Server developers and/or administrators the tricks of the trade. Sometimes you come across a GEM, a question that you can blog about so that when they are asked again, you have a well constructed answer. One classic questions asked by new database developers is whether or not the user input is a number? I thought it was an excellent opportunity to review what tools are available given a…