MDK. The Guile integration is progressing quite fast. I quickly discarded the C++ wrapper thing: the C interface is clear enough, and i didn't see a way of improving it in C++. By now, i'm able to interact with the MIX virtual machine from within a guile shell and the other way around: interpret scheme commands from the vm command prompt. This opens great possibilities, like implementing new functionality usin scheme... in short, MDK is beginning to be extensible. I plan to write new scheme extensions to access the MIX vm, and a little scheme lib for manipulating the MIX data types in the next few days, and then make a new release.
Tools. I've begun to use on a regular basis a tool to keep todo lists from the command line, devtodo, and found it really useful (thanks to fxn). A second wonderful discovery has been surfraw, a refreshing project consisting of a set of scripts to access common WWW search engines from the command line: don't miss the web page, it's worth reading!