RSS 
Well, as promised, I've finished the first version of the little Lisp project I've been working on and it's only mid June. So with no further adu, I present cl-pack.
cl-pack is a Common Lisp library supplying perl/php/ruby compatible pack() and unpack() functions so that Lisp can easily communicate with those languages via binary protocols or files. pack() and unpack() take Lisp data and pack them into binary strings that can be stored or exchanged safely with other programs. The (un)pack functions are handy utilities that most other common languages support and now so does Lisp.
Cavets: This is the first release, therefor full coverage of all pack() syntax isn't yet available. Most data type (all common ones) are supported, as are repeaters in the form of numbers and '*'. Grouping with brackets and other extended syntax is not yet supported, but should be forthcoming in the next release. Documentation is in cl-pack.lisp and if you want to see what it can do, also look at tests.lisp. cl-pack is ASDF compatible so it should integrate with your system well. It relies on ieee-floats but ships with a copy should your system be lacking one.
You can get it at ftp.mindstab.net/cl-pack
So yeah, this is what I've been working on for the past month or so. Glad to get it out. I plan to throw up some small web page for it in a few days and then start working on the remaining syntax support.
Edit: I set up a page for cl-pack at CLiki http://www.cliki.net/cl-pack
