1. By 2050 we may not be needing any input output devices like keyboard, mouse, touchscreen or touch pads. Your thoughts are enough to type, search or do any task on your computer which you normally do with your I/O devices. It also means that you will have to mask yourself from TTs or Thought Tress-passers who will try to steal your thought and try to read your mind without your knowledge and try to know your secrets. This will also lead to a new type of mind-hacking where hackers will try to gain access to your personal and financial details over the web with the help of some social hacking. Companies like google who search keywords from your emails to judge what ads might interest you, may start browsing your mind and see what you really need and what you really want. Future matchmaking will be much easier with automated soft-wares with access to your minds may find a proper match for you on your favorite matrimonial or dating site. The product you may want to watch out in this segment is NeuroSky Mindset with its future variations. We will be able to do most of the daily tasks such as changing the temperature of the refrigerator, changing tv channels, send mails typing, browsing etc., with just our thoughts. People with bionic limbs will be able to control them with their thoughts without having to rely on dumb prosthetic limbs.
2. Our vehicles are auto-piloted, our body parts can be replaced with mechanized/digitized versions which can be controlled, shutdown or damaged remotely by people with vested interest and of course we know people who tried to warn us about it got a mysterious death like the hacker barnaby jack.
3. The biggest invention any civilization can make is communicating with itself back in time. We all have thought at some point in our life that I wish I knew this earlier, I wish I could go back in time and tell myself about this to a younger version of me so that I could avoid certain things. Assuming that human kind has survived and thrived in future, this method already exists. So future us is communicating, educating us to speed up our civilization's progress. So if this communication happens with someone who predates the existence of any long distance real time communication like today then they will for surely think that it was the voice of god or an angel and may be start a religion based on that. What if all the knowledge in all the holy texts was just the future us trying to make the past and present us wiser than what we are and we only were able to digest the higher level of context of the text!!!???
---more such nonsense for later... :P