Remove / expire accounts when E-mail not confirmed on time?

[peteruithoven]

A user might have selected his/her perfect username, but then make a typo in the E-mail address. In this case the user can't confirm the account, and the username is reserved. Shouldn't it be possible to remove unconfirmed accounts after ... hours?

People having an issue like this with other projects:

• https://productforums.google.com/forum/#!topic/youtube/PHa9ksjWVVY
• http://wordpress.stackexchange.com/questions/160633/how-can-i-un-reserve-a-pending-username-registration

While doing research into this I understand I could use the requireEmailConfirm config option option. This would probably make for a more friendly solution, where a user gets limited access, but can change it's E-mail and resend the confirmation mail. But for this to work I'd need to check the existence of an email field beside checking the roles field during authorizations. Seeing that this is more work, having accounts expire would still be interesting.