Not dynamic : Data ranges become redundant when new records are added, resulting in established formulae needing to be altered. Overlooking these errors can be embarrassing and downright expensive, especially if important decisions are being made based on the data.
A winning spreadsheet could make you a fortune. If you could effectively identify what many people want and are willing to pay for, and can make your spreadsheet easily accessible, you could be cashing checks for the rest of your life.
You'll need to develop good marketing material. Things like demo videos, which you can find plenty examples on YouTube, screenshots, and keyword rich descriptive text help people find your spreadsheet and communicate the value that sets yours a level above the rest. Excelville.com actually allows you to upload your spreadsheet with all of this marketing material in an easily searchable and user friendly website.
Another advantage to using a spreadsheet application for your budget is that you won't have to access the Internet to access your budget. You will be able to view it or work on it wherever you are and if you typically work on a laptop computer and take it with you when you travel, this can be extremely beneficial. Using budgeting spreadsheets to manage your finances is an easy and affordable way to stay on top of your financial game.