microdlna
A simplistic filesystem-based DLNA server
...No search capabilities, no sorting, no thumbnails, no format conversion, but no need for management, reindexing, and no heavy dependencies either.
"Do one thing and do it well."
Basically it's a fork of MiniDLNA stripped down to the level of tftpd :D.
Please note that until version 1.0 it is at most a beta, so be paranoid about it, eg. create a dummy user that has no write access to anything precious and use that to run MicroDLNA, etc.