README.md in matheus-0.4.0 vs README.md in matheus-0.5.0

@@ -14,9 +14,16 @@
 $ alert-me 'sleep 1 && echo "Done!"'
 Done!
 # plays a sound after the command finishes
 ```
 
+### [`convert-currency`](./lib/matheus/convert_currency.rb)
+
+```sh
+$ convert-currency usd eur
+1 USD = 0.92 EUR
+```
+
 ### `date-of-last`
 
 Prints the date of the last week day.
 
 ```sh