Found the below at...
Using the CONCATENATE function
Yet another option was suggested to me by B. Ganesh: Use the CONCATENATE function. In this case, each argument for CONCATENATE consists of an IF function.
Here's an example:
=CONCATENATE(IF(A1="A",1,""),IF(A1="B",2,""),IF(A1="C",3,""),
IF(A1="D",4,""),IF(A1="E",5,""),IF(A1="F",6,""),IF(A1="G",7,""),
IF(A1="H",8,""),IF(A1="I",9,""),IF(A1="J",10,""))
The CONCATENATE function can handle as many as 30 arguments -- which equates to testing 30 different conditions.
And, as Alan Williams pointed out, you can avoid using the CONCATENATE function and use the concatenation operator (&):
=IF(A1="A",1,"")&IF(A1="B",2,"")&IF(A1="C",3,"")
&IF(A1="D",4,"")&IF(A1="E",5,"")&IF(A1="F",6,"")
&IF(A1="G",7,"")&IF(A1="H",8,"")&IF(A1="I",9,"")
&IF(A1="J",10,"")
This method is not limited to 30 comparisons.
Ron