The times of ASCII as a widely used text format are mostly gone by now. Web is all multimedia. Emails are pretty often HTMLed. Books are in MS Word format or some ebook crap. Documentation is PDFed. Some people do use ASCII (plain text), but they are getting less and less.
ASCII Generator is a lot of fun for those who still use ASCII. It converts a word or a phrase of your choice into a piece of plain text using one of many ASCII fonts. The results can be used on the web, or as a part of email signature.
NOTE: Don’t forget that you’ll need fixed/monospace font to replicate the results in most of the graphical programs. And even than you will most probably still have problems with tabs and spaces. Good luck.