[dba-Tech] Incremental Backups - large files

Does anyone have any experience with incremental backups of large files.

I have a 1 GByte TrueCrypt encryption "volume file", i.e. the file that gets
mounted as an encrypted volume by the TrueCrypt program.  It contains my
billing and other company confidential data.  I want to do a backup to get
the file off of my laptop every night.  I am wondering if doing an
incremental backup on a file that size would take a "very long time"
(nebulous definition I know).  Does anyone have experience with backing up
large files?

John W. Colby
Colby Consulting
www.ColbyConsulting.com