A very simple application that takes in an array of links and generates a link that redirects to one of those links at random.
The application just encodes the values of the inputs in base64 (btoa), joins them with & and appends them to the base URL as a hash.
If the entry URL contains a hash, the application picks the parts (split by &), picks an element at random and attempts to parse it (atob). If it is successful, the user is redirected to that page.
Did I already say it was very simple?