Nuclear Nova Software (http://www.nuclearnova.com) says its ASCII Art for Mac OS X (10.5 and higher) is now available through the Mac app store. It’s on sale for US$9.99 (normally it’s $19.99). The software is Universal Binary so runs natively on both PowerPC and Intel Macs.
ASCII Art is a generator that converts digital pictures into text art. You can output art to both black/white text and full color, with the ability to export plain text, HTML, TIFF and RTF files. A user editable character set adjusts the available characters to be used. ASCII Art offers real time previews.
Compatible source images include JPEG, PNG, GIG, BMP, TIFF, TGA, JPEG, TIF and more. Output quality greatly depends on the input file. Often images such as clip art work better than sources such as digital pictures.