1) MP3 Player: I think this tool has changed the way we listen to music.it's light, quick and cheaper than older similiar tool.
2) Memory card: This tool allows us to easily transfer large amounts of data on pc mobile phones and digital camera.
3) Computer: This is one of the greatest inventions in the history of humanity.
4) Mobile phone : this tools has changed the way of calling, surfing on the internet, take photos and videos, playing.
5) Microwave oven: this invention has made cooking faster and easier.
Stefano