Percona XtraBackup is an online (non-blocking) backup solution for InnoDB engines. It features uninterrupted transaction processing during backups for InnoDB, but can also backup MyISAM tables.

mylvmbackup is a script for quickly creating backups of MySQL server's data
files. To perform a backup, mylvmbackup obtains a read lock on all tables and
flushes all server caches to disk, makes an LVM snapshot of the volume
containing the MySQL data directory, and unlocks the tables again. The snapshot
process takes only a small amount of time. When it is done, the server can
continue normal operations, while the actual file backup proceeds.