We use this on two other forums I post on, and it's wonderful.
It's an extra BBcode add-on, but there hasn't seemed to be any issues with it. Here is a link to a thread that shows the functionality at the bottom of the first post - though I'm sure you've seen it before: http://www.vbulletin-faq.com/forum/s...de-Spoiler-Tag

Could be useful for hiding oversize pics, or spoilered info for anything.

Just a thought.