Thanks to everyone for pointing out that RIAForge was down today. Where's all the email when the sites aren't down, eh??? ;)
So what was wrong? The site uses a temporary folder to store data extracted from SVN when folks view/download from Subversion via the web site.
Guess what - that temporary folder had not been emptied since the dawn of Man.
Yes - this is something I've blogged about before - watching disk space - and I've just been bitten by it myself!