I’ve had emails sent to me with attached files labeled “final” or “final revision”. In the past I’ve done this myself. The problem with attaching the word “final” to any file is that it’s never final. There will always be some tweak, color adjustment, typography change, kerning, spacing, etc. to the project that will warrant updating the file name. This is where it can get funny. I’ve had files come my way called, “Document X Final 6”. If you have to add a number to the word final, is it really final? My simple advice is to lose that word from your vocabulary when it comes to projects. You’ll save face when it comes time to renaming your files. Consider going with a convention such as “revision X”. Then, if you get into double digits with revisions the name of the file will be the least of your worries.