I've encountered the rude awakening a few times myself. Once, at a company that had no DBA, just "the SQL boy," a manager issued a DROP TABLE statement by accident on a database in bulk-logged recovery mode. The transaction logs had never been backed up, and were 300GB on 20GB of data. We soon realized that in order to restore last week's backups (because they took so long they were only done on weekends), the 100GB free was insufficient, and needed some creative space management and several days of data transfers on a severely overloaded and badly designed system. They ended up regenerating the missing data over a three week period because it was faster. They didn't lose ALL their customers...