tYp3r

Link: http://typ3r.aavi.me

Input

This is a normal sane piece of text written by the author of this tool. 
What you do with it is none of my business.

Output

dIS 1S a NoRMaL sAnE PIeC3 0F t3xT wrITTEN bY da AuThoR oF thIS TO0l.
waT u D0 wid 1T iZz noNe of maH BuS1neSs.

Contribute

The conversion library (typ3r.js) used by this tool is at aviaryan/typ3r.js. Please send patches in that project.

PS - Contributing is simple, see index.js file. It has all the required transformations. Editing it is as easy as editing a JSON file.

---

Thanks to @anshumanag on Twitter for the idea.