<A target="_blank" href="http://www.andypedisich.com/blogs/andysblog.nsf/dx/transaction-logging-heres-some-stuff-to-keep-in-mind.htm">Andy Pedisich enabled circular transactional logging</A> on his 8.5 server only to have it crash with a "log full" error. He's posted the list of databases that should not have logging enabled and directions on disabling it for individual files.