We all want to be able to communicate with each other in total privacy. So we need lots of good random numbers to do that using cryptography. And true random numbers are the most secure. My interest is making entropy sources using simple and commonly available components like webcams and Zener diodes. These can then be the foundations of your own true random number generators (TRNGs) you can rely on to not have been compromised by governments or their agencies.
Or things like this Photonic Instrument, which produces entropy at over 200kb/s:-
Visit http://www.reallyreallyrandom.com to see it running on-line.