I know that most stackexchange site urls are subdomains under stackexchange.com, such as android.se and unix.se.
Do the legacy sites (namely Stack Overflow, Super User and Server Fault) and others (e.g. http://askubuntu.com) also have a subdomain under stackexchange that would forward to their site?
If not, should they? I could see it being useful to have the option of all sites under one domain, and redirecting to or from the original unique domains.