Google Apps offers an excellent email service for businesses, anybody having a domain name can offer anyemail@theredomain.com email accounts with full Gmail features by just changing a few MX record entries in there DNS options and configuring there web-applications to use Google's server for emailing.

To ensure better email delivery rate to user's inbox avoiding chances of being tagged as SPAM, there are systems in place which allows email sending server to verify email origin (a sort of digital signature) and let SPAM categorization algorithms decide whether the email is sent from a fake "From" origin address or a real one.

Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) are two such measures and here is how to set them up for emails originating from Google Apps servers for your domain.

Online whistleblowing site Cryptome leaked an internal Microsoft document "Microsoft® Online Services Global Criminal Compliance Handbook" having information regarding what user-activity records Microsoft keeps for their online services and for how long in compliance with legal authorities, the site labeled the document microsoft-spy.zip but was soon taken down by their hosting provider after receiving an DMCA copyright infringement take-down notice from Microsoft.

However, the site is now back online and still hosts the microsoft-spy.zip along with various other "spying guides" like yahoo, Paypal, MySpace and Facebook to name a few.