Poke is a feature led by facebook to get attention of any user, well you can compare it wit the Buzz option we had in Yahoo Chat, so we used to click on Buzz and then the other person's chat used to vibrate and make sounds to get their attention, its somewhat same but yes off course it does not make your screen vibrate but if leave a notification without any message or anything but just saying that person poked you and you can poke him back to say yes I remember you :)
So now manually poking back to many person's might be a big problem so we have simple solution to this thing by making this process automatic. Now we have two options by which you can make this thing automatic. The one is by using the chrome extension that will work only in chrome and the other one is Userscript that will work in both Chrome and Firefox.
Auto Poke Back using Chrome Extension
Well Poke All for Chrome extension gives you the possibility to poke all your friends back all together with one click. Well yes it even has that automatic feature which you can select and every poke will be reverted back automatically. So now you can install this extension only in chrome.
So now after installation just visit Facebook and click on this hand icon in your status bar now you c will see all your pokes you can select Auto Poke or just click on the Poke All option.
Auto Poke Back using UserScript
Well there is even a simple userscript that can be installed in Chrome, Firefox and Opera browser, so Facebook Autopoke userscript does the same job but its totally automatic. So you will need Greasemonkey installed in your Firefox browser to get this script working.
For the chrome browser you can install this script directly but you will need to follow this easy tutorial on installing 3rd party extension and scripts in chrome.
So that's it now you can every Poke you receive will be reverted back automatically, if you find any problem do comment.