We have wildcard support. Just specify a hostname like '*.example.com' when buying a cert :-)

Amazing. What about the proper file creation? (Although that's not that hard with a couple of calls to "cat" but getting the order right is hard for people who haven't done it before).

Yup, we create three cert files for every purchase:

www.example.com.crt - the certificate by itself

www.example.com.chain.crt - the intermediate certificate

www.example.com.chained.crt - concatenation of the certificate and the intermediate certificate

Most software, including nginx, takes the .chained.crt file. Apache takes the .crt and the .chain.crt file as separate config options.