CF_Random_Pass is one of my older tags but it gets more use than any of them. It was initialy designed to generate unique passwords but I have, since, found many different uses for it. The tag will generate a random string as long as you wish it to be. You may also specify the character sets to be used in the string. Read the Docs to learn more.

BHCaptcha is my solution to bots who scour the web for comment forms in an attempt to place their useless links and absurd information among the valid comments that our visitors were gracious enough to leave. I'm sure you've seen web forms that place randomly generated text images next to a field. You have to read the image’s content and enter it into a text field to submit the form. Well, that is what BHCaptcha is. Only, BHCaptcha is 100% self contained ColdFusion code. There is no need for a third party image tag to generate the images for you. Read the documentation for more details or help with BHCaptcha.