Just wanted to plug my OWN project. 
This isn’t strictly SDL related, but it is intended for game writers, and
with all the recent talk about packfiles and such on this mailing list,
this might be handy to someone:
PhysicsFS is meant to give you an abstraction over the filesystem and
archives like ZIP files. It’s also a good way to secure file i/o from your
game. It’s largely inspired by the Quake 3 filesystem routines (and some
enhancements Bernd Kreimeier, Nicholas Vining and myself did to them for
FAKK2), but was completely written from scratch and LGPL’d. Adding support
for a new archive type is as simple as filling in a few functions and
plugging it in.
…and other cool stuff.
Comments and code contributions welcome.
–ryan.