My site, which gets slightly less traffic than Less Wrong, makes me $50-$200 per month with Amazon referral links and no advertising at all. I don't profit this way, but I recoup some of my costs.
I think the Less Wrong audience is much more likely to purchase books - including expensive textbooks - than my audience is. And it would be easy to automatically transform all Amazon links on Less Wrong so that they include a Less Wrong Amazon Associates referral code, which would make Less Wrong some money on every purchase made through one of those links.
Below is the pseudocode, assuming Less Wrong's Amazon Associates referral code is "lesswrong". Note that every Amazon page for an item contains at least the following string: "/dp/XXXXXXXXXX/" where XXXXXXXXXX is alphanumeric.
if hyperlink contains "*amazon.com*/dp/??????????/" then change hyperlink to "http://www.amazon.com/dp/??????????/ref=nosim?tag=lesswrong-20"
That's it! For example, let's say somebody wrote a post and pasted in the following Amazon hyperlink from their browser's address bar:
http://www.amazon.com/Artificial-Intelligence-Modern-Approach-3rd/dp/0136042597/ref=sr_1_1?ie=UTF8&qid=1296058194&sr=8-1
This would be transformed into:
http://www.amazon.com/dp/0136042597/ref=nosim?tag=lesswrong-20
This is precisely what I do on my own site. Works like a charm. If somebody clicks my book link but ends up buying a $1000 DSLR instead, I get about $65 for that one purchase.
Somebody who didn't give up programming in 8th grade could do this fairly easily I imagine, and it would help cover Less Wrong's expenses.
It looks like LW's Amazon affiliate code is "vglnk-c319-20". I missed it earlier because apparently VigLink doesn't work if you control-click on a link to open it in a new tab. I've written a Chrome/Greasemonkey user script you can install to add the affiliate code to Amazon.com links you click on other web sites, as well as if you go to Amazon.com manually.
http://www.ibiblio.org/weidai/force_amazon_affiliate.user.js