I've seen in the past questions on the meta dealing with case specific problems that have been very intriguing, yet to find out that the linked question had been deleted resulting in the "Page not found!" prompt.
After one of these questions are raised to view, they are usually deleted soon thereafter, leaving the Meta-post as a blob of text, with little reference to the post, which doesn't seem all that great. I don't want to ramble so I'll keep this brief.
I think there should either be a cache of the question saved when deleted so that it can be referenced, or some way to view said questions (see below.) Thoughts?
EDIT:
As pointed out by @Serg when reaching 10,000 reputation or more, you can view deleted answers, however I feel it would be good for new users to see these ridiculous mistakes being called out, so that they would know what not to do when it came to asking a question.
votes
filter and then go to the last page, these are the most downvoted questions on the site, some could learn form these, I like to read them and find funny ones askubuntu.com/questions?page=4780&sort=votes