I use BackBlaze at home and they do a great job.  Not only do they have great online backup service, they also sponsor World Backup Day.  Walter Mossberg just did a nice review of them.  They do both consumer and business backups.  They also do some really nice blog posts about reliability of hard drives and how they run their business.

 

Their backup saved my bacon as the HD on my old iMac died.  I had an external drive I backed up to with Time Machine, but it turned out that drive had errors as well.  The online backup ended up doing the trick.  Glad I was using belt and suspenders :)