https://bitbucket.org/wolfpld/etcpak/wiki/Home - A very fast ETC texture compressor. Being 80x-500x faster than every other compression utility (with not that much quality difference) was quite fun.
https://bitbucket.org/wolfpld/usenetarchive - A set of tools to process and view large collections of usenet/mailing list messages. For example, an archive of polish usenet is 56+ million messages.