Hi, I'm sorry, but I must be asleep or dreaming while giving you the previous answer... zzz... ![#-o]( "d'oh!")
Please disregard my previous answer...
Actually, you can point to multiple external hard disk drives as your Destination in a single profile. The trick is to get it to always point to the correct drive, as Windows tends to auto-assign a different drive letter to whatever drive that is plugged in. So Ext Drive A could have a drive letter assigned to it now, but when you remove Ext Drive A and insert Ext Drive B, a different drive letter might be assigned to it.
You could try this method:
http://www.2brightsparks.com/bb/viewtopic.php?f=15&t=9731&p=38210
to rename the drives so that they have the same Volume Label (and the other rule is that you can only have one drive connected at a time when you run the common profile).
Bear in mind you must not use profiles that use state-memory to record the contents of one or both sides (Fast Backup or SmartSync), as you would be telling a profile the previous-state of one drive should be taken into account regarding decision-making when you swap in the other drive (with an older/different state).
But standard Backup or Mirror profiles should work OK, because they only work on 'state-now' (comparison of corresponding contents right then). Versioning is also possible, because Versions are enumerated 'on the fly' so each run would enumerate the Versions on the Destination device that is connected, and act accordingly.
Please disregard my previous answer...Actually, you can point to multiple external hard disk drives as your Destination in a single profile. The trick is to get it to always point to the correct drive, as Windows tends to auto-assign a different drive letter to whatever drive that is plugged in. So Ext Drive A could have a drive letter assigned to it now, but when you remove Ext Drive A and insert Ext Drive B, a different drive letter might be assigned to it.
You could try this method:
http://www.2brightsparks.com/bb/viewtopic.php?f=15&t=9731&p=38210
to rename the drives so that they have the same Volume Label (and the other rule is that you can only have one drive connected at a time when you run the common profile).
Bear in mind you must not use profiles that use state-memory to record the contents of one or both sides (Fast Backup or SmartSync), as you would be telling a profile the previous-state of one drive should be taken into account regarding decision-making when you swap in the other drive (with an older/different state).
But standard Backup or Mirror profiles should work OK, because they only work on 'state-now' (comparison of corresponding contents right then). Versioning is also possible, because Versions are enumerated 'on the fly' so each run would enumerate the Versions on the Destination device that is connected, and act accordingly.