Having an e-mail address
Fragment of a discussion from User talk:Kephir
Ah, not the reason I expected! I mainly find myself annoyed by systems that *don't* accept e-mail and require something else (e.g. Facebook or other proprietary non-standard system). If you're genuinely having trouble finding a free (throwaway or otherwise) mail account then you're welcome to have one on one of my domains; I've had some of them for about 15 years now, scarily enough, so they tend to stay around.
I don't need it for anything but I had considered sending you an e-mail :) Lucky escape.