Backup software required - Advice Needed

I am looking for some software to use for a backup system, but I was just wondering if there is any software that can syncronise 2 drives rather than simply clone drives, etc.

My reasons are, I have a 500GB external desktop drive and a smaller portable external drive and I would like to keep them both sync'd so they both contain the same files (for when I'm away from home, etc).

Would prefer a free app but don't mind paying if it'll do what I need it to do, and would prefer there to be a windows and mac version available, but that's not crucial.

Thanks

kfordham281 said:

ChronoSync: http://www.econtechnologies.com/site/Pages/ChronoSync/chrono_overview.html

Click to expand...

Thanks. That looks like a good app. Does anyone know of a Windows equivelant?

Thanks