One thing that really did it for me was programming something where you would normally use floats (audio/DSP) on a platform where floats were abysmally slow. This forced me to explore Fixed-Point options which in turn forced me to explore what the differences to floats are.
What Every Computer Scientist Should Know About Floating-Point Arithmetic - https://news.ycombinator.com/item?id=3808168 - April 2012 (3 comments)
What Every Computer Scientist Should Know About Floating-Point Arithmetic - https://news.ycombinator.com/item?id=1982332 - Dec 2010 (14 comments)
What Every Computer Scientist Should Know About Floating-Point Arithmetic - https://news.ycombinator.com/item?id=1746797 - Oct 2010 (2 comments)
Weekend project: What Every Programmer Should Know About FP Arithmetic - https://news.ycombinator.com/item?id=1257610 - April 2010 (9 comments)
What every computer scientist should know about floating-point arithmetic - https://news.ycombinator.com/item?id=687604 - July 2009 (2 comments)