There is a free online service called Blog Backup Online which can be used to take daily backups of your blog. Presently, it supports platforms like Blogger, WordPress, LiveJournal, Friendster, Movable Type, Multiply, Serendipity, Terapad, TypePad, Vox, and Windows Live Space. Blog Backup Online is still in Beta. For taking backup users get 50 MB space per account.
You can also save the backup in your harddisk. According to BlogBackupOnline now taking backup of your blog has become three step process
1) Sign up on Blog Backup Online
2) Register the blog you want to back up
3) Your blogs are automatically backed up daily.
