Haiku version of 'setmime' command-line tools has some unimplemented features. The one is icons support. The goal of this task is to bring the setmime tool to production level by finishing implementation.
 
Your Task is:

• Implement support (dump and set) of MINI, LARGE and VECTOR icons. Format of output should be identical to BeOS version of setmime;
• Improve handling of attribute type - currently it supports only alphanumeric types output ('CSTR' for example) - types that are not rerpesentable as printable characters should be dumped and accepted in hexadecimal form (0x53542356 for example);
• supress printing any info in -dumpIcon or -dumpSniffRule for types having, correspondently no Icons or SnifferRules;

Links:
http://siarzhuk.dyndns.org/setmime-gci-kit-08.12.2011.tar.bz2 - standalone version of setmime tool project;

http://haiku-os.org/legacy-docs/bebook/BMimeType.html - BMimeType reference;

http://haiku-os.org/development - info for Haiku development;
https://www.haiku-os.org/development/coding-guidelines - Haiku Coding Guidelines;

http://siarzhuk.dyndns.org/setmime.zip - BeOS version of setmime binaries. To run this on Haiku you have to replace your /boot/system/lib/libbe.so with customized library available here:
http://siarzhuk.dyndns.org/libbe.so.bz2

Good luck and feel free to ask your mentor for any additional information and materials!