I've been reading up on SharePoint high availability and disaster recovery lately. In my search for resources, I came across this very recent TechEd presentation by Neil Hodgkinson, called SharePoint Business Continuity Management. Neil is a senior program manager and knows quite a bit about the Microsoft Office server products.
In the discussion, Neil talks about the SQL Server and SharePoint features that apply specifically, such as failover clustering, database mirroring, log shipping (which isn't too difficult to configure, I've found), and AlwaysOn Availability Groups.
Check it out and get educated!