Mongoose
https://github.com/cesanta/mongoose/
Mongoose is released under commercial and GNU GPL v.2 open source licenses. The GPLv2
open source License does not generally permit incorporating this software into non-open
source programs. For those customers who do not wish to comply with the GPLv2 open source
license requirements,Cesanta Software offers a full, royalty-free commercial license and
professional support without any of the GPL restrictions.
Tremor
http://wiki.xiph.org/index.php/Tremor
BSD license