Question: Is there a PNG viewer that can display text chunk metadata? Ideally, I'd like a way to view arbitrary chunks.

Answer: 
Found a partial solution, the [pngcheck](http://www.libpng.org/pub/png/apps/pngcheck.html) tool can print text chunks although it wont display the image.

```
pngcheck -c -v -t foobar.png

```

These are the relevant options for showing PNG chunks:

```
-7  print contents of tEXt chunks, escape chars >=128 (for 7-bit terminals)
-c  colorize output (for ANSI terminals)
-p  print contents of PLTE, tRNS, hIST, sPLT and PPLT (can be used with -q)
-t  print contents of tEXt chunks (can be used with -q)
-v  test verbosely (print most chunk data)

```
The ImageMagick "display" program will do it. Display the image with **display *filename*.png**, hold the right button to bring up the menu, select **Image info**, and scroll down.