A Haskell implementation of the product-remainder tree in the paper Mining Your Ps and Qs: Detection of Widespread Weak Keys in Network Devices. This implementation takes roughly 2.5 seconds to process 10,000 of 1024 bit RSA public keys on an average home computer.
Assuming moduli.hex contains hex-encoded moduli to be factored, one of each line. Runing cabal run . --ghc-options="-threaded -Wall" -- moduli ./moduli.hex ./save.txt should save results to save.txt.