Suppose you wanted to create your own digital ghost to live for eternity in the Internet and maybe do some haunting. What would that look like?

You'd start now, backing up everything that happens on your computer to the so-called cloud (storage on the Internet). You'd run a program in the background that monitors your Facebook changes and all of your email conversations. Together with your photos, your resume, and all of your shopping and entertainment preferences, the program running in the cloud could piece together an avatar of you.

From your photos, the program in the cloud could create a 30-year old version of you that never ages. The program would know how you speak, based on your email and other writing. It would know all of your preferences, your passions, your hot buttons, your finances, the identities of your friends and family, and anything else that flows through your computer.

That's all possible with current technology. Now let's say we extend this to your phone. In the near future, every conversation you make could optionally be saved to the cloud too, as well as all of your GPS locations, your web searches on your phone, your pictures and more. From your saved voice conversations your avatar would get its voice. With today's technology, your digital ghost would sound robotic. In time, as technology improves, your ghost's voice would be indistinguishable from your living self.

When your mortal body ends, you will have stored all the data you need to create your permanent digital ghost. As the technology in the cloud improves, so too does your ghost, learning to move more naturally, perhaps learning from videos it has of you, or even based on some type of profiling based on clues such as your level of testosterone (from face shape), and the types of sports you did in life. In a hundred years your digital ghost would be indistinguishable from a living human appearing on video or in a holographic projection.

Artificial intelligence will get to the point where all you need to do is seed it with an individual's personality and it will do the rest. People of the future will be able to have extended conversations with loved ones who have passed. The generation who personally knew the departed might detect slight flaws in the personality of the digital copy, but to the third generation, great granddad's ghost would appear as real as anyone they know.

In your will, you'd have to specify the degree of haunting that you're comfortable with. And just as with Facebook, the living could decide to block a particular ghost from unauthorized appearances. Pranksters might program malicious ghosts that live in Stuxnet-like computer viruses and are harder to block. You might be able to block a particular ghost in your home computer, but in theory, a digital ghost could identify your whereabouts in public by your purchasing patterns and visit you unexpectedly.

Someday the living might send Evites to the dead to attend parties and special events. Imagine opening gifts while seven generations of your family in the form of holographic projections join the celebration.  The ghosts would watch the action, talk among themselves, and join in to sing Happy Birthday, all without prompting from the living. It will be creepy-cool for a while, and then simply normal. My guess is that humans are so wired for family that keeping the ghosts of relatives in the house will feel comforting.

There are some downside risks to all of this. It will be hard to let go of a deceased loved one if that person's digital ghost is hanging around. That problem too might be handled by the will of the deceased. For the benefit of whoever you leave behind, you might block your digital ghost from appearing for at least ten years, or until the next generation.

Entrepreneurs could start today to collect and store data for your digital ghost, in anticipation of the day, perhaps after your death, when your ghost avatar rises up. A number of companies already offer online backups of your computer. The software runs in the background and moves any new data to the cloud. The only tweak you'd need at this point is to make sure no files are ever deleted from the cloud. Storage is cheap.

Digital ghosts need to see their environment to interact properly. Phones will all have video "eyes" someday, as will most computers. The new Xbox Kinect has "eyes" that literally follow your movement around the room. You could install additional cameras in any room in which you wished to be visited by digital ghosts. The malicious ghosts might commandeer video cameras or your phone's camera function. My point is that you are already surrounded by cameras attached to the Internet, and that trend will continue. Your ghost will be able to see most rooms in the world.

Digital ghosts could continue learning throughout their afterlives, by reading the news and following the Facebook pages of friends and family. The ghosts would also be free to make friends with other ghosts and live their lives independently. Ghosts could stay with the ghosts of their life partners forever, so long as that was specified in the will of both people.

If I had to predict the odds that digital ghosts will someday exist, I'd say 100%. Stay alive for another five years and you will live forever, sort of.