Should you ever desire to touch an object that is off limits for some reason, you will benefit from a few of the tactics that I have gathered in my observations of Dominic. This is pure will, unspoiled by the experience of life. He is not even one yet! Here is how he would advise you:
The first method is, of course, the easiest. Simply touch the object. There is no need for subtlety or stealth. If this should fail, wait until the "guard" looks away and then attack.
Now, if the direct method is not working, perhaps you should resort to using a secondary object. I would recommend something familiar like a stuffed Doggy or sippy cup but in a pinch blocks or a little book will work. Here's how this works. While you are playing near it, casually drop your Doggy or cup onto the keyboard, trying your best to make it look like an accident and then, as you pick up your Doggy, extend the time it takes to pick it up as long as possible by grazing all of the keys and pressing a few if you can manage.
While the keyboard is clearly the most fun, it is still fun to touch any part of a computer. I like to try to poke the screen with one finger or come up to the computer from the back side and feel the logo. But my very favorite is to come up along the side of the keyboard and try to eat the side with all of the holes for things. If you can't get to the keyboard, the power cord is also very tasty, especially the little end.
I have just a few more tricks for you. Though of course you cry whenever they strike down your efforts with, "No" and a hand slap, cry whenever you walk by the computer, even if nobody says, "No". It will get you some sympathy and maybe they will let up their vigilance. Try to rest your head on the laptop, as if you are really, really tired. They think that's cute. My most recent tactic, though, is my special invention. It's called hover hands. Here's how you do it. Hold you hands about two inches above the keyboard for about thirty seconds moving them back and forth but making it clear that you are not touching the keyboard. Then, when you have them convinced, drop your hands onto the keyboard. Presto!
Just be sure that you don't get in trouble when you actually weren't trying to get the computer. For example, as happened to me yesterday, if you happen to lose your balance and your hand accidentally falls upon the keyboard, straighten up immediately and put your offending hand straight up in the air away very dramatically and away from the computer. "Hands up" they call it.