Polymath4 is devoted to a question about derandomization: To find a deterministic polynomial time algorithm for finding a k-digit prime. So I (belatedly) devote this post to derandomization and, in particular, the following four problems.
1) Find a deterministic algorithm for primality
2) Find a combinatorial characterization (and a deterministic algorithm) for generically 3-rigid graphs
3) Find an explicit construction for Ramsey graphs
4) Find a deterministic method for polling
(Remark: I was very slow in writing this post, and I had to give up elaborating the details on some very nice topics in order to finish it.)