Gmail has a function that really hasn't been advertised enough, so I'll do the work for them. Google allows you to add as many stuff behind a + in your e-mail, for example if your Gmail address is:

john.doe@gmail.com

Well, then you can transform it into:

john.doe+mailinglists@gmail.com

Any mail you send to that address still arrives at john.doe@gmail.com, so you only have to register that one. Here comes the fun part: the "sent to" header has changed, so now you can add a filter that automatically applies a label or marks the message as spam, all you need to do is click "Add filter" and write in the second form (To:): john.doe+mailinglists@gmail.com. No more need for registering additonal addresses, unless the smarter spam senders realise this and automatically delete the part between + and @, only a small change in the code.