People who want to stay on top of the UK terror alert level can sign up to receive periodic e-mail updates from MI5. Sorta but not quite, since MI5 has outsourced managing the e-mail service to an American company. See: MI5 terror alert blunder sends private data to US mailshot firm | the Daily Mail.
This is not a disaster, but clearly the UK intel folks didn't think about the perception of doing things this way.
What's the lesson here? When you are dealing with personal information, think about every facet of how the service is being offered and how it may be perceived.
Update (20070117): According to Spy Blog, MI5 is now handling its email subscriptions in-house.