CPAN Testers is really a mailing list with a web interface, testers.cpan.org. testers.cpan.org was painfully slow. I happened to be doing metadata stuff for Module::CPANTS. This is the result. It's alpha code, but using it anyone can host their CPAN Testers website.
Actually, I've just checked it this morning and testers.cpan.org is still horribly slow. Getting all the distributions which begin with 'A' takes 50 seconds for testers.cpan.org and 0.4 seconds for testers.astray.com. This is because I generate static files.
Actually implementing it was fun. The turning point where everything suddenly started being clear was realising that testers.cpan.org was really an interface to the NNTP archive of the cpan-testers mailing list. The rest was done using Net::NNTP, Email::Simple, caching, DBD::SQLite, Sort::Versions and the Template::Toolkit.
It obviously needs a little design work and some computer-readable way of reading results. Anyone got some spare time?
Phew, that's secret project number one down...