Other Erdős problem lists

- Most significantly Erdős' Problems on Graphs is a project very similar to this, although only for those problems related to graph theory. It contains 170 graph theory problems posed by Erdős, with references and commentary.
- Wikipedia has a list of some.
- Here is a list of the problem collections published by Erdős.

Other Erdős-related links.

- You can find out the Erdős number of any mathematician with this free tool provided by the AMS.