solarkennedy

I have a comparison of these tools going here: http://www.xkyle.com/a-comparison-of-image-to-ascii-conversi...

I can add this to the list, but it looks like it does not take advantage of the half-block trick to double the effective vertical resolution. (like other tools like img2xterm)

tacone
If you need monochromatic images (ie for logos or charts) a pretty cool trick is using braille. With a little bit of hacking, the xkcd example of this repo https://github.com/asciimoo/drawille/ works pretty well :)

I'll be using this for my email signature.