The graph below is from the SEOptimise blog showing what happened to a new site after building 10,000 spammy links to it in a single day. What happened was the site tanked in rankings just after a few weeks.

He said:

Is it about the bad links? Is it about the site being new and ranking due to QDF temporarily?

New data shows the site is now back in the top 10, after taking a dive in rankings.

This case study is continually building upon itself in the comments. There are just so many factors, it is hard to isolate the issue or issues. The site is new. It has 10,000 horrible links. The links are all spammy, 99% of them. The site is now ranking well again. The site may be based in the UK.

Here are some good comments from the post:

Anyway, if anything, it is always fun to watch people destroy things.

Forum discussion at Sphinn.