As yet, no site outages due to our hosting provider, www.hostgator.com. It has been quite solid since before November 2004 (I'm not entirely sure I know when this site was created.)
On 6/8/2015-6/9/2015, we had an outage due to the upgrade of the Perl CGI.PM module used by our wiki software. Special thanks to Gordon L at Hostgator who went above and beyond to offer a fix for the code. We were down about a day.