In the early 1980s Douglas Lenat wrote EURISKO, a program Eliezer called "[maybe] the most sophisticated self-improving AI ever built". The program reportedly had some high-profile successes in various domains, like becoming world champion at a certain wargame or designing good integrated circuits.
Despite requests Lenat never released the source code. You can download an introductory paper: "Why AM and EURISKO appear to work" [PDF]. Honestly, reading it leaves a programmer still mystified about the internal workings of the AI: for example, what does the main loop look like? Researchers supposedly answered such questions in a more detailed publication, "EURISKO: A program that learns new heuristics and domain concepts." Artificial Intelligence (21): pp. 61-98. I couldn't find that paper available for download anywhere, and being in Russia I found it quite tricky to get a paper version. Maybe you Americans will have better luck with your local library? And to the best of my knowledge no one ever succeeded in (or even seriously tried) confirming Lenat's EURISKO results.
Today in 2009 this state of affairs looks laughable. A 30-year-old pivotal breakthrough in a large and important field... that never even got reproduced. What if it was a gigantic case of Clever Hans? How do you know? You're supposed to be a scientist, little one.
So my proposal to the LessWrong community: let's reimplement EURISKO!
We have some competent programmers here, don't we? We have open source tools and languages that weren't around in 1980. We can build an open source implementation available for all to play. In my book this counts as solid progress in the AI field.
Hell, I'd do it on my own if I had the goddamn paper.
Update: RichardKennaway has put Lenat's detailed papers up online, see the comments.
One problem with this argument is how conjunctive it is: "(A) Progress crucially depends on breakthroughs in complexity management and (B) strong recursive self-improvement is impossible and (C) near-future human level AGI is neither dangerous nor possible but (D) someone working on it is crucial for said complexity management breakthroughs and (E) they're dissuaded by friendliness concerns and (F) our scientific window of opportunity is small."
My back-of-the-envelope, generous probabilities:
A. 0.5, this is a pretty strong requirement.
B. 0.9, for simplicity, giving your speculation the benefit of the doubt.
C. 0.9, same.
D. 0.1, a genuine problem of this magnitude is going to attract a lot of diverse talent.
E. 0.01, this is the most demanding element of the scenario, that the UFAI meme itself will crucially disrupt progress.
F. 0.05, this would represent a large break from our current form of steady scientific progress, and I haven't yet seen much evidence that it's terribly likely.
That product comes out to roughly 1:50,000. I'm guessing you think the actual figure is higher, and expect you'll contest those specific numbers, but would you agree that I've fairly characterized the structure of your objection to FAI?