You can group your access points (WIFI,3g, GPRS, etc) and set priorities on which should be tried first.
This can help to save money if you prefer to use WIFI for downloading email but want it to still work on the move without changing settings.
I use it with mail for exchange for syncing my calendar and contacts with Google on My E71 :)
Info: http://www.birdstep.com/Products/Birdstep/SmartConnect/
But use the nokia app download feature on your phone, search for "smartconnect" in the ovi store.