I didn't grow up near the ocean, so when I learned to dive in the Pacific in '96, I had a real *bleagh* experience with the taste of saltwater. Thus, I started wearing my biking camelback (backpack water bladder with suck tube and bite valve) on my chest when I dove, so I could remove my reg and take a drink or rinse out my mouth any time I wanted.
After about 5-8 dives I got used to the taste of the seawater, and haven't even thought of taking the camelback underwater since. Now, I don't even notice the salt.