There are at least two spam filtering services that protect their customers while getting visual verification right from an accessibility point of view. Spam Arrest provides a clearly audible equivalent of the characters to be entered in order to pass the verification test while provides an e-mail copy of the numeric code to be entered. Through personal experience, I am aware that both services have provided accessible visual verification systems for at least four years. This is clear evidence that there is absolutely no excuse for ongoing inaccessibility in the area of visual verification! If you are looking for a sure way to block spam from your inbox, I strongly recommend the use of either Spam Arrest or 0Spam over lesser companies that might block blind people from sending you e-mail.