With Windows PowerShell you can now back up your SharePoint Site Collections either one off or using scripts that can be scheduled.
Although you can use the Central Administration to back up your site collection as a once off task, you get additional options using Windows PowerShell, such as using SQL Snapshots for backing up SharePoint 2010 Site Collections.
Backup-SPSite http://server_name/sites/site_name -Path C:\Backup\site_name.bak
Get-SPSiteAdministration http://server_name/sites/site_name | Backup-SPSite -Path C:\Backup\site_name.bak
Backup-SPSite http://server_name/sites/site_name -Path C:\Backup\site_name.bak –UseSqlSnapshot
Note: You can use the UseSqlSnapshot parameter only if you are hosting your content database on SQL Server Enterprise Edition / SQL Server Developer Edition.
Windows PowerShell also gives you the flexibility of backing up several site collections using the thread parameter.