This one comes straing from the archives of LifeClever, a blog aimed at being a career guide.
You (yes, YOU) must have come across a friend, family member, or just some enthu guy/gal who told you to let go of all negativity. Replace all the “won’t”, “can’t”, “don’t” from your talk into “will”, “can”, “do” instead. Well, today I bring you (with the help from LifeClever ‘ocourse) a true Jedi mind trick. I especially like this trick, because instead of forcing brain to come up with the antonyms of words to turn those “won’t” into “will” or “cannot” into “can”, this trick makes the whole process extremely simple and a LOT more productive in the end.
I’m a big fan of Google’s “define:” functionality (in google search, type define: life to see it). Recently, Google released a dedicated dictionary page, so I thought I’d create a nice little Firefox keyword bookmark to do this from the address-bar itself. And here’s how this works:



Now every time you want to get a definition of something, all you have to do is type define [your_word] in the address bar, and see the most current definition come up!

(NOTE: this snapshot shows address bar with “define firefox” in it, but that will change automatically once you hit return. I just left it there so you can see what to type.)
Google offers dictionaries for A LOT of languages. 
So you may choose to do this with endef (for English definition) spdef (for Spanish) gudef (for Gujarati) and whatever have you!
I hope this helps some of you! Let me know if you come up with some fun hacks of your own :)