I've found that although arrays are not intuitive to most Excel users they can come in very handy at times. For example, a VLOOKUP formula similar to the one below might be a good alternative to beating the limitations of a nested IF statement.

=VLOOKUP(A1,{1,"Jan";2,"Feb";3,"Mar";4,"Apr";5,"May";6,"Jun";7,"Jul";8,"Aug";
9,"Sep";10,"Oct";11,"Nov";12,"Dec"},2,FALSE)

Here are two variations:

=INDEX({"Jan”,"Feb”,"Mar”,"Apr”,"May”,"Jun”,"Jul”,"Aug”,"Sep”,"Oct”,"Nov”,"Dec"},A1)
=CHOOSE(A1,"Jan”,"Feb”,"Mar”,"Apr”,"May”,"Jun”,"Jul”,"Aug”,"Sep”,"Oct”,"Nov”,"Dec")