Here's an interesting case: a site was hacked. The hackers installed a Pligg clone, posted thousands of spam stories and then used the site as part of a link wheel - building even crappier links to the spam stories.
The intrusion was spotted too late (the hosting provider ended up paying a compensation but that's a different story) and now the site has tens of thousands toxic links pointing to it.
The only saving grace is that after the cleanup, the toxic links point to 404s.
Luckily there are no toxic links pointing to the homepage or the legitimate content/tools/graphs/whatever.
There's no way anyone can remove the bad links. How would Google view this situation? What would you do?
Relax and carry on or try to disavow the toxic links even though they don't pass any link juice?