David Pogue of the New York Times last week raised a simple but interesting point about the short messages carriers tack on to the end of your voicemail greeting. In most instances, after your pre-recorded greeting, the alerts tell a caller to your voicemail inane things like "at the tone, please record your message" (Verizon) or "when you are finished, you may hang up" (AT&T). Pogue notes these aren't just there for convenience, but --and this may surprise you about the wireless industry -- to milk consumers out of money:While there are keys to bypass these useless messages, they're usually different for each carrier. Interestingly, Pogue notes that Apple made AT&T pull the greeting for iPhone users. He also notes that Sprint does allow users to remove the added carrier greeting if they're willing to navigate through a few layers of voicemail settings. For those carriers who continue to use the little scheme, Pogue links to their various complaint forms in his blog entry.