[0x0]

Here's another article which starts with a .c program and refines it through a series of improvements to end up with a very tiny elf executable:

http://www.muppetlabs.com/~breadbox/software/tiny/teensy.htm...

Manually picking out hex opcodes is maybe a bit over the top. A nice assembler like nasm should be "low level enough" while still providing a lot more convenience and flexibility.

[kunai]

Well of course, nobody writes any applications in hex; it's more of a proof of concept, but a very interesting proof of concept.

Asm, at least for me, is still too low-level for me to do any sort of serious work. I make desktop/mobile apps, and don't really do any sort of kernel hacking, so currently, I'll stick with C++ and Java. It is a nice thing to know, however, I don't see myself learning it right now. It's inevitable that I'll have to learn it sometime in the future if I ever want to broaden my prospects, but it's nice to play around with, but isn't all too useful for me.