I've used celery with a few django and flask projects. It's nice, but it added a lot of overhead for me. So I've used http://flower.readthedocs.io/en/latest/ to help handle the monitoring.
For some really small sites and very specific use cases, I actually wrote some small custom helper scripts to just have cron jobs.
If you are using django, I found this library helpful. https://bitbucket.org/wnielson/django-chronograph/