One of the things I worry about most when it comes to small businesses is disaster recovery. For a lot of small businesses, the disaster recovery plan revolves around the owner’s Visa limit, and that's a terrible position to be in. One of the key considerations to any disaster recovery plan is regular backup, and that can be a tough sell at many SMBs, but the difficulty makes it no less critical.
One of the companies here at TechEd is showing a novel approach to SMB e-mail backup: Cemaphore Systems is using Google Apps for the backup back end, and keeping the process transparent for users with Exchange servers. The essential concept is simple, mirroring all e-mail traffic from the Exchange server to Google's server through Cemaphore's SaaS framework. MailShadow for Google Apps is in Beta right now, but you can sign up to be considered for inclusion, and it seems like an interesting approach to the problem. If you do sign up, let me know how it works for you – I'll keep you posted from this end.