There are a lot of different schools of thought on administering programming tests to new hires. On one hand, youre hiring them to program, so it might be nice to see if they can actually do it. On the other hand, given the time constraints of most interviews , its nearly impossible to give them a meaningful test.

From that conflict grows tests like FizzBuzz. Greg Qs company uses the old reverse a string method. Neither of these is a good test of an experienced programmer, but its a quick way to weed out the worst incompetents.

Like, for example, this applicant for a Senior Developer position:

private void button1_Click(object sender, EventArgs e)
{
        string a = "A";
        string b = "B";
        string c = "C";
        string d = "D";
        string f = "E";

        MessageBox.Show(a + ", " + b + ", " + c + ", " + d + ", " + f + ", \n"
                + f + ", " + d + ", " + c + ", " + b + ", " + a);
        }
}

http://thedailywtf.com/articles/backwards-interview