Using Excel to model formulas and algorithms is my obsession!

I've worked as a Business Analyst in the financial software sphere for years, and have frequently used Excel to model various business formulas and algorithms. In fact, once people know what I'm capable of, they usually look at me as the Excel Go-To guy. I'm very familiar with the common functions, like IF, SUMIF, VLOOKUP and HLOOKUP. But I'm also familiar with some others that many users probably never knew about, including:
--String manipulation functions, including, CONCAT, FIND, LEN, MID, RIGHT, LEFT & TRIM. These are especially handy for those times when you're reading a .CSV file (comma-delimited file) into Excel, and want to parse it to get some information out of it.
--The INDIRECT function, which lets you create the name of a cell using formulas and functions, and then reference the (numerical/string) value that resides within that cell. This is quite powerful, for occasions where the cell name itself is not easily known upfront, because it depends upon the result of a formula.
Moreover, in order to expand my knowledge of Excel--and because I was a programmer in a former life ;) --I've taken it upon myself to learn VBA (Visual Basic for Applications, which is a programming environment "bolted onto" the Excel package). This is invaluable for those times when an algorithm requires indefinite looping. While such iterations are certainly possible inside Excel proper (i.e., a spreadsheet), they are just messy and inelegant, as you end up using all kinds of extra space in a spreadsheet, much of which may be wasted. The user then has to cull through--or ignore--all the garbage. Having a scripted programming language to work in greatly increases the utility of the software package.
WARNING (Truth in Advertising): I've had precious little experience with Pivot Tables! So please don't tap me for that. My focus is on formulas and algorithms, and capturing them succinctly, whether in a spreadsheet, a VBA SUB procedure, or a VBA Function procedure.