Guile's looking much better than it did the last time I used it. The boot time is only a couple of seconds now, and the core engine seems to do everything you'd want a Scheme to do. Guile doesn't support R4RS macros, but it does have LISP-style macros, which are marginally less elegant and far more powerful.

Threads seem to be broken. The following result is just a little bit bogus:

guile> (use-modules (ice-9 threads))
guile> (begin-thread 10)
ERROR: In expression (call-with-new-thread (lambda () #) (lambda args args)):
ERROR: Unbound variable: call-with-new-thread
ABORT: (misc-error)

Anybody know what happened to call-with-new-thread? It seems to be missing in action.

I'm waiting to hear back about the Guile licensing policy. Ideally, Guile shouldn't require all Scheme programs to fall under the GPL. No other scripting language has the audacity to force such terms on users (MegaCorp Visual AppBuilder: you must give us rights to all programs which run under our system), and it probably wouldn't stand up in court.

If the licensing terms on Guile aren't acceptable, I'll start digging around for another Scheme interpreter. I need macros and threading at a minimum, and it must be possible to write Scheme programs under the author's choice of licensing terms. If performace on a 16MB 486 were borderline acceptable, that would cinch the deal.

Check out Rasterman's progress on Enlightenment 0.14. The Linux community seems to be reopening many areas of research in computer science, which is a good thing--the field has been getting boring of late, and no small number of researchers despair at ever seeing their work implemented.

Happy news! The motherboard for our Linux robot arrived today, and it looks really sweet. Unfortunately, it sucks power like there's no tomorrow. On the bright side, it comes with a short-term battery, a power supply, three serial ports, a parallel port, a PS/2 keybord port, a 486 SX, one SIMM slot, one ISA slot, one PCI slot, a floppy bay (which conflicts with the ISA slot) and a notebook drive bay. The case measures approximately 10x7x3.5. For a hundred dollars, this would make a smashing microserver. We have the notebook drive, and are scrounging a SIMM and an Ethernet card. The other good news comes from Jim Blandy, the author of Guile:

No, Guile places no requirements on scripts you write. You can put them under any license you please. It's the same with GCC: GCC places no requirements on your source code, or the object code it generates.

Good luck!