See if you've done this:

You're stopped at a light, trying to get the attention of the person next to you. When you catch their eye, what do you do? You pretend to grasp a crank handle and turn it rapidly in a circle to make the universal roll-down-your-window gesture.

There's only one problem.

Almost nobody "rolls down" their window like that anymore. That once-needed skill has all but disappeared.

It's hardly the only example.

Thanks to the rapid march of technology, a slew of once-needed technical skills are disappearing faster than dial-up Internet service. And now, in honor of those vanishing tech skills, there is an Australian Web site — http://www.obsoleteskills.com — devoted to their memory. Some of the skills that have been left in the digital dust are decades old, such as dialing a rotary phone. Other skills are disappearing as we speak, such as adjusting the tracking on your VCR.

Here are just some of the obsolete or rapidly disappearing technologies and the skills that go with them.

- Changing the ribbon on a typewriter

- Rewinding audio or video cassettes

- Adjusting the rabbit ears on your TV set

- Checking your beeper

- Formatting a floppy disk

- Having to put www in front of every URL

- Loading film into a camera

- Using a darkroom

- Licking stamps

- Paying with a check

- Using a pay phone

- Looking up a business in the Yellow Pages

- Switching from TV to Game Mode on the box behind the TV

- Blowing into a dusty Nintendo cartridge to make it work

- Using the Dewey Decimal System to find a book

- Winding your watch

- Long division (other than for school)

- Calling the radio station to find out what song that was

- Ripping the trim with the holes off the sides of computer paper

- Calling someone collect

- Replacing tape in your answering machine

- Threading a filmstrip

- Popping popcorn with hot oil

- Heating a "TV Dinner" in the oven

- Getting up to manually change the channel

- Repairing a television set

- Sharpening a razor blade

- Adding water to car batteries

- Riding a single-speed bike

- Setting the time on a VCR

- Downloading music from the original Napster

- Putting tape over the punched-out holes on a VCR tape so you can use it again

- Using correction fluid

- Putting a nickel on the tone arm of a record player to keep it from skipping

- Placing the needle at the beginning of a song on a vinyl record without making a scratching noise

- Popping in a flash cube

- Using a choke

- Cleaning a vinyl record

- Defrosting the refrigerator

- Refilling a fountain pen

- Using carbon paper to make copies

- Changing tracks on an 8-track tape

- Taping songs off the radio onto a cassette tape

- Sniffing freshly mimeographed tests

- Sending a handwritten letter

- Writing in cursive

- Mowing the yard with a non-powered push mower (May be coming back, though ...)

- Milk deliveries

- Manually entering prices into an old-fashioned cash register

- Cleaning the head of your VCR

- Crawling under the door of a pay toilet