Yes, definately. I had a contract late last year that, for some reason not easily discernable for us mere mortals, the client wanted to change from an existing Visual Basic application to an Oracle solution within an Excel document.
I was required to produce PL/SQL and SQL code to replace the Visual Basic code and wrap the entire script in the Excel wrapper. I passed information between PL/SQL and Excel via macros and finalized the script that was run via macros written specifically to supply variable information and structure.
One brief tip – use nested SQL rather than cursors if possible. They seem to run faster and you don’t have to worry about managing the cursor or attendent memory structures. It takes a bit longer to get the correct nested SQL, but it is well worth the effort.