The company I worked for asked me to port an old deprecated module from 4.7 to 5 because no one within the community had done so yet.
The CitizenSpeak module allows the creation of email petition campaign nodes.
Due to the large amount of changes in the Form generation in Drupal, there was quite a bit of work to be done to get it going on Drupal 5. I did test the module quite thoroughly, but as many developers know, you'll need to see it working under a heavy load before you can say for sure that it works well.
You can check it out here.