As a complete derail:

Floating point, as IEEE standard? Beautiful. Elegant. One of my favorite technical standards. Other than the +0/-0 thing, it's perfect.

Floating point, as implemented? Ugh. You've got processors which implement some subset of x87, MMX, SSE, SSE2, SSE4, and AVX, all of which handle floating point slightly differently. Different rounding modes, different precisions, different integer conversions. Calling conventions differ between x32 and x64. Using compiler flags alone on Linux x64, you can make 'printf("%g", 1.2);' print 0. Figuring out the intermediate precision of your computations takes a page-sized flowchart: http://randomascii.files.wordpress.com/2012/03/image6.png

It's a mess.