One way to deal with the broken links due to Nabble's change of host name
As people noticed, Nabble changed the subdomain name of this forum.
This is very unfortunate, as Coursera students like me would not be directed to this site (I thought this site was down forever...).
Even worse, a lot of links included in the posts become broken. Although you can ask the authors to change it, some of these posts are updated long ago so it is not very likely all these would be updated soon.
In case you don't know or don't remember, you can use a HTTP redirect tool in your browser to replace "32033.n3.nabble.com" (old nabble site domain) with "52.s1.nabble.com" (current nabble domain) when the url contains something like nand2tetris-questions-and-answers-forum. In this way the broken links will work again.