For listing jobs added by at and batch I use atq, but it lists only my jobs. I can run atq with root privileges and then it lists jobs from all users.
How can I list all jobs without root privileges?
This may not be the answer you want, but strictly speaking, you could boot a Live CD and use that to look at the files in /var/spool/at (or equivalent).
The privacy and security provisions of Unix/Linux does not allow you to do what you want. The at files are stored by default with "other" read privilege set to off.
you might create a custom little program that runs atq and give it suid root.
beware that: