Discussion about http://opengameart.org/content/abuse-art, in particular about the relevant fileformat(s). I'll update this post as I figure out more information. Sorry if it's painful to read, but the forums strips indentation - code tags, anyone?

Most Abuse content is in .spe files, a little endian format that contains image data, palettes, levels and more.

8 SPEC1.0\0
2 number of entries
1 type of entry
1 length of...
x ...name. \0 terminated
1 a flag of some sort; I don't think this was ever implemented, and probably had to do with linking files...?
4 data size
4 data offset (absolute)

Type 21 - Sprites
----------------------------
2 width
2 height
(width * height)
1 index color
1 flags
bit meaning
1
2
3
4 polygon 2 contact damage
5
6
7
8
1 vertical offset?
1 horizontal offset?
1 number of points of polygon 1 (contact polygon)
1 x
1 y
1 number of points of polygon 2
1 x
1 y

Type 2 - Palettes
-----------------------------
2 number of colors
1 red component
1 green component
1 blue component