This is just a fun hack that uses various Unicode characters to make text look like it was flipped upside down.
The mapping is based on one from revfad.com, but I extended it with most of the uppercase characters. This page isn't done with JavaScript, but you can see the upside-down character mapping
Originally found via a referrer log entry pointing to reddit.com.
| Original Text |
|---|
| Mwar? |
| Upside-down Text |
| ¿ɹɐʍW |