I find it frustrating that long postings have a scroll-bar on the right side, because this means that whenever I try to print (or "print to PDF" as available in MacOS) many messages are partially cut-off.
I've never had this problem with other forums, so I keep asking myself what the point of those scroll-bars are anyway -why not just display each message at its full length?
Failing that, how about adding a "print" button on each page which will allow anyone to print the entire discussion thread.