This week has been filled with them. The following threads are examples that I can think of.
https://www.fakku.net/viewtopic.php?p=589109#589109
https://www.fakku.net/viewtopic.php?p=589104#589104
https://www.fakku.net/viewtopic.php?p=589069#589069
https://www.fakku.net/viewtopic.php?p=588976#588976
https://www.fakku.net/viewtopic.php?p=589124#589124
https://www.fakku.net/viewtopic.php?p=584778#584778
https://www.fakku.net/viewtopic.php?p=588796#588796
https://www.fakku.net/viewtopic.php?p=588822#588822
https://www.fakku.net/viewtopic.php?p=588858#588858
https://www.fakku.net/viewtopic.php?p=584816#584816
https://www.fakku.net/viewtopic.php?p=584801#584801
https://www.fakku.net/viewtopic.php?p=584740#584740
https://www.fakku.net/viewtopic.php?p=584835#584835
https://www.fakku.net/viewtopic.php?p=584831#584831
https://www.fakku.net/viewtopic.php?p=584804#584804
https://www.fakku.net/viewtopic.php?p=584793#584793
https://www.fakku.net/viewtopic.php?p=584782#584782
On the plus side, threads that get revived (be it intentional or not) can be good for re-starting discussions on said thread, because the topic can be interesting.
On the negative side, new threads can get disregarded, or "buried", rather quickly in some cases because of said necrobumps. That can make things harder to find for example, like in the user upload section. Let's face it, not everyone uses the masterlist to find what they are looking for.