Sign up for an online webmail account for things like passwords and so on and then you are never tied to your service provider and its set email addys.
I'd go grab a Gmail or Yahoo UK account and just have it all sent to that one instead. And then keep it for other online stuff also.
Erm, I've no idea if this is doable. I don't use TheArseOfTheIntern... I mean MySpace, I loathe it but on similar sites you can usually change the default email addy easy enough as long as you can still log into your account wherever it is.