Using FastMail on my own domains. One account covers all the domains. Having more domains costs the same as one. They support several different kinds of address aliasing/wildcarding (including Gmail style '+' wildcards and multiple recipient). Their DNS is absolutely great with useful defaults.
FastMail is pretty excellent, particularly if you like running mail off your own domains with Gmail-style wildcard address support and really fancy DNS. You get what you pay for.
Never looked back.