diff --git a/README.md b/README.md
index 286d975..dfcbcaa 100644
--- a/README.md
+++ b/README.md
@@ -21,3 +21,9 @@ For all TLDs in tld.txt, try *.string.tld
 ```
 for tld in $(cat tld.txt); do cat middle_segments.txt|awk '{print $1".'$tld'"}';  done|pv -l |xargs node try_url.js
 ```
+
+Get a list of hashes which have not yet been identified
+
+```
+comm -23 <(sort -u data/current.txt) <(awk -F= '{print $1}' data/identified.txt |sort -u) > todo.txt
+```