Add tags to landing page to trigger smart campaign

Our company develops and supports software.  We offer a broad selection of products.  We would like to be able to flag landing pages with a specific product so we can send auto responses related to the product in which the prospect was researching.  We would also like to be able to use this for scoring.

I thought about using the URL and adding perhaps a mix of letters and numbers like a code, but we kind of like having control over what we create as a URL as we like them to be friendly.

I have tried looking up a way to use a hidden token that I can trigger off of, but from what I read there are issues with trigger tokens.  Thought perhaps interesting moments would work, but would still need something on the landing page that I can trigger off of.  I know there has to be a way to do this!

Is there a way to trigger a page off of a token in the meta data of a page?  Is there a way to add a hidden token to a page?