When dealing with lookup tables, rather than typing "Lookup Table Name" in formulas, add another parameter such as "LTN" with the associated CSV file and use that within the formulas. And as a bonus, if you want to use multiple lookup tables within the same family, add a couple of parameters - "LTN01", "LTN02","LTN03"..... and just add the lookup files names in the value column. If you have standardized parameters and standardize lookup table columns, copy the family and simply replace the lookup file names and your family is complete! (This works well with such parts as NHCI sort sweeps, quarterbends, eighth bends, etc... if you have them as separate families.)

Another use would be for information used in graphics such as data entry into charts, graphs, and forms. You can use macros (VBA) to convert Excel spreadsheet information into CSV file format and then use it in your Revit families. IE: one excel file which contains information used on every project that varies with each project. assign a number unique to each project and locate all the project specific information on that line under the appropriate headers - treat it like a part fitting family!