I have used methods such as this with CGI. I needed to pass values in URLs such as session IDs and user IDs. Using methods such as this, a long session ID becomes a short char string. It also, in my opinion, helps disuade people form putting "random" stuff into your URLs in the hope that something interesting is seen (I know that this won't stop someone with the relevant skills, but it might stop the wannabes).

I agree with the previous comment that in native storage you gain nothing, but you can save space in other situations (such as URLs in e-mails where a long URL may wrap and become confusing).

== fx, Infinity Is Colourless